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diff --git a/venv/lib/python3.11/site-packages/sqlalchemy/dialects/postgresql/asyncpg.py b/venv/lib/python3.11/site-packages/sqlalchemy/dialects/postgresql/asyncpg.py
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+# dialects/postgresql/asyncpg.py
+# Copyright (C) 2005-2024 the SQLAlchemy authors and contributors <see AUTHORS
+# file>
+#
+# This module is part of SQLAlchemy and is released under
+# the MIT License: https://www.opensource.org/licenses/mit-license.php
+# mypy: ignore-errors
+
+r"""
+.. dialect:: postgresql+asyncpg
+    :name: asyncpg
+    :dbapi: asyncpg
+    :connectstring: postgresql+asyncpg://user:password@host:port/dbname[?key=value&key=value...]
+    :url: https://magicstack.github.io/asyncpg/
+
+The asyncpg dialect is SQLAlchemy's first Python asyncio dialect.
+
+Using a special asyncio mediation layer, the asyncpg dialect is usable
+as the backend for the :ref:`SQLAlchemy asyncio <asyncio_toplevel>`
+extension package.
+
+This dialect should normally be used only with the
+:func:`_asyncio.create_async_engine` engine creation function::
+
+    from sqlalchemy.ext.asyncio import create_async_engine
+    engine = create_async_engine("postgresql+asyncpg://user:pass@hostname/dbname")
+
+.. versionadded:: 1.4
+
+.. note::
+
+    By default asyncpg does not decode the ``json`` and ``jsonb`` types and
+    returns them as strings. SQLAlchemy sets default type decoder for ``json``
+    and ``jsonb`` types using the python builtin ``json.loads`` function.
+    The json implementation used can be changed by setting the attribute
+    ``json_deserializer`` when creating the engine with
+    :func:`create_engine` or :func:`create_async_engine`.
+
+.. _asyncpg_multihost:
+
+Multihost Connections
+--------------------------
+
+The asyncpg dialect features support for multiple fallback hosts in the
+same way as that of the psycopg2 and psycopg dialects.  The
+syntax is the same,
+using ``host=<host>:<port>`` combinations as additional query string arguments;
+however, there is no default port, so all hosts must have a complete port number
+present, otherwise an exception is raised::
+
+    engine = create_async_engine(
+        "postgresql+asyncpg://user:password@/dbname?host=HostA:5432&host=HostB:5432&host=HostC:5432"
+    )
+
+For complete background on this syntax, see :ref:`psycopg2_multi_host`.
+
+.. versionadded:: 2.0.18
+
+.. seealso::
+
+    :ref:`psycopg2_multi_host`
+
+.. _asyncpg_prepared_statement_cache:
+
+Prepared Statement Cache
+--------------------------
+
+The asyncpg SQLAlchemy dialect makes use of ``asyncpg.connection.prepare()``
+for all statements.   The prepared statement objects are cached after
+construction which appears to grant a 10% or more performance improvement for
+statement invocation.   The cache is on a per-DBAPI connection basis, which
+means that the primary storage for prepared statements is within DBAPI
+connections pooled within the connection pool.   The size of this cache
+defaults to 100 statements per DBAPI connection and may be adjusted using the
+``prepared_statement_cache_size`` DBAPI argument (note that while this argument
+is implemented by SQLAlchemy, it is part of the DBAPI emulation portion of the
+asyncpg dialect, therefore is handled as a DBAPI argument, not a dialect
+argument)::
+
+
+    engine = create_async_engine("postgresql+asyncpg://user:pass@hostname/dbname?prepared_statement_cache_size=500")
+
+To disable the prepared statement cache, use a value of zero::
+
+    engine = create_async_engine("postgresql+asyncpg://user:pass@hostname/dbname?prepared_statement_cache_size=0")
+
+.. versionadded:: 1.4.0b2 Added ``prepared_statement_cache_size`` for asyncpg.
+
+
+.. warning::  The ``asyncpg`` database driver necessarily uses caches for
+   PostgreSQL type OIDs, which become stale when custom PostgreSQL datatypes
+   such as ``ENUM`` objects are changed via DDL operations.   Additionally,
+   prepared statements themselves which are optionally cached by SQLAlchemy's
+   driver as described above may also become "stale" when DDL has been emitted
+   to the PostgreSQL database which modifies the tables or other objects
+   involved in a particular prepared statement.
+
+   The SQLAlchemy asyncpg dialect will invalidate these caches within its local
+   process when statements that represent DDL are emitted on a local
+   connection, but this is only controllable within a single Python process /
+   database engine.     If DDL changes are made from other database engines
+   and/or processes, a running application may encounter asyncpg exceptions
+   ``InvalidCachedStatementError`` and/or ``InternalServerError("cache lookup
+   failed for type <oid>")`` if it refers to pooled database connections which
+   operated upon the previous structures. The SQLAlchemy asyncpg dialect will
+   recover from these error cases when the driver raises these exceptions by
+   clearing its internal caches as well as those of the asyncpg driver in
+   response to them, but cannot prevent them from being raised in the first
+   place if the cached prepared statement or asyncpg type caches have gone
+   stale, nor can it retry the statement as the PostgreSQL transaction is
+   invalidated when these errors occur.
+
+.. _asyncpg_prepared_statement_name:
+
+Prepared Statement Name with PGBouncer
+--------------------------------------
+
+By default, asyncpg enumerates prepared statements in numeric order, which
+can lead to errors if a name has already been taken for another prepared
+statement. This issue can arise if your application uses database proxies
+such as PgBouncer to handle connections. One possible workaround is to
+use dynamic prepared statement names, which asyncpg now supports through
+an optional ``name`` value for the statement name. This allows you to
+generate your own unique names that won't conflict with existing ones.
+To achieve this, you can provide a function that will be called every time
+a prepared statement is prepared::
+
+    from uuid import uuid4
+
+    engine = create_async_engine(
+        "postgresql+asyncpg://user:pass@somepgbouncer/dbname",
+        poolclass=NullPool,
+        connect_args={
+            'prepared_statement_name_func': lambda:  f'__asyncpg_{uuid4()}__',
+        },
+    )
+
+.. seealso::
+
+   https://github.com/MagicStack/asyncpg/issues/837
+
+   https://github.com/sqlalchemy/sqlalchemy/issues/6467
+
+.. warning:: When using PGBouncer, to prevent a buildup of useless prepared statements in
+   your application, it's important to use the :class:`.NullPool` pool
+   class, and to configure PgBouncer to use `DISCARD <https://www.postgresql.org/docs/current/sql-discard.html>`_
+   when returning connections.  The DISCARD command is used to release resources held by the db connection,
+   including prepared statements. Without proper setup, prepared statements can
+   accumulate quickly and cause performance issues.
+
+Disabling the PostgreSQL JIT to improve ENUM datatype handling
+---------------------------------------------------------------
+
+Asyncpg has an `issue <https://github.com/MagicStack/asyncpg/issues/727>`_ when
+using PostgreSQL ENUM datatypes, where upon the creation of new database
+connections, an expensive query may be emitted in order to retrieve metadata
+regarding custom types which has been shown to negatively affect performance.
+To mitigate this issue, the PostgreSQL "jit" setting may be disabled from the
+client using this setting passed to :func:`_asyncio.create_async_engine`::
+
+    engine = create_async_engine(
+        "postgresql+asyncpg://user:password@localhost/tmp",
+        connect_args={"server_settings": {"jit": "off"}},
+    )
+
+.. seealso::
+
+    https://github.com/MagicStack/asyncpg/issues/727
+
+"""  # noqa
+
+from __future__ import annotations
+
+import collections
+import decimal
+import json as _py_json
+import re
+import time
+
+from . import json
+from . import ranges
+from .array import ARRAY as PGARRAY
+from .base import _DECIMAL_TYPES
+from .base import _FLOAT_TYPES
+from .base import _INT_TYPES
+from .base import ENUM
+from .base import INTERVAL
+from .base import OID
+from .base import PGCompiler
+from .base import PGDialect
+from .base import PGExecutionContext
+from .base import PGIdentifierPreparer
+from .base import REGCLASS
+from .base import REGCONFIG
+from .types import BIT
+from .types import BYTEA
+from .types import CITEXT
+from ... import exc
+from ... import pool
+from ... import util
+from ...engine import AdaptedConnection
+from ...engine import processors
+from ...sql import sqltypes
+from ...util.concurrency import asyncio
+from ...util.concurrency import await_fallback
+from ...util.concurrency import await_only
+
+
+class AsyncpgARRAY(PGARRAY):
+    render_bind_cast = True
+
+
+class AsyncpgString(sqltypes.String):
+    render_bind_cast = True
+
+
+class AsyncpgREGCONFIG(REGCONFIG):
+    render_bind_cast = True
+
+
+class AsyncpgTime(sqltypes.Time):
+    render_bind_cast = True
+
+
+class AsyncpgBit(BIT):
+    render_bind_cast = True
+
+
+class AsyncpgByteA(BYTEA):
+    render_bind_cast = True
+
+
+class AsyncpgDate(sqltypes.Date):
+    render_bind_cast = True
+
+
+class AsyncpgDateTime(sqltypes.DateTime):
+    render_bind_cast = True
+
+
+class AsyncpgBoolean(sqltypes.Boolean):
+    render_bind_cast = True
+
+
+class AsyncPgInterval(INTERVAL):
+    render_bind_cast = True
+
+    @classmethod
+    def adapt_emulated_to_native(cls, interval, **kw):
+        return AsyncPgInterval(precision=interval.second_precision)
+
+
+class AsyncPgEnum(ENUM):
+    render_bind_cast = True
+
+
+class AsyncpgInteger(sqltypes.Integer):
+    render_bind_cast = True
+
+
+class AsyncpgBigInteger(sqltypes.BigInteger):
+    render_bind_cast = True
+
+
+class AsyncpgJSON(json.JSON):
+    render_bind_cast = True
+
+    def result_processor(self, dialect, coltype):
+        return None
+
+
+class AsyncpgJSONB(json.JSONB):
+    render_bind_cast = True
+
+    def result_processor(self, dialect, coltype):
+        return None
+
+
+class AsyncpgJSONIndexType(sqltypes.JSON.JSONIndexType):
+    pass
+
+
+class AsyncpgJSONIntIndexType(sqltypes.JSON.JSONIntIndexType):
+    __visit_name__ = "json_int_index"
+
+    render_bind_cast = True
+
+
+class AsyncpgJSONStrIndexType(sqltypes.JSON.JSONStrIndexType):
+    __visit_name__ = "json_str_index"
+
+    render_bind_cast = True
+
+
+class AsyncpgJSONPathType(json.JSONPathType):
+    def bind_processor(self, dialect):
+        def process(value):
+            if isinstance(value, str):
+                # If it's already a string assume that it's in json path
+                # format. This allows using cast with json paths literals
+                return value
+            elif value:
+                tokens = [str(elem) for elem in value]
+                return tokens
+            else:
+                return []
+
+        return process
+
+
+class AsyncpgNumeric(sqltypes.Numeric):
+    render_bind_cast = True
+
+    def bind_processor(self, dialect):
+        return None
+
+    def result_processor(self, dialect, coltype):
+        if self.asdecimal:
+            if coltype in _FLOAT_TYPES:
+                return processors.to_decimal_processor_factory(
+                    decimal.Decimal, self._effective_decimal_return_scale
+                )
+            elif coltype in _DECIMAL_TYPES or coltype in _INT_TYPES:
+                # pg8000 returns Decimal natively for 1700
+                return None
+            else:
+                raise exc.InvalidRequestError(
+                    "Unknown PG numeric type: %d" % coltype
+                )
+        else:
+            if coltype in _FLOAT_TYPES:
+                # pg8000 returns float natively for 701
+                return None
+            elif coltype in _DECIMAL_TYPES or coltype in _INT_TYPES:
+                return processors.to_float
+            else:
+                raise exc.InvalidRequestError(
+                    "Unknown PG numeric type: %d" % coltype
+                )
+
+
+class AsyncpgFloat(AsyncpgNumeric, sqltypes.Float):
+    __visit_name__ = "float"
+    render_bind_cast = True
+
+
+class AsyncpgREGCLASS(REGCLASS):
+    render_bind_cast = True
+
+
+class AsyncpgOID(OID):
+    render_bind_cast = True
+
+
+class AsyncpgCHAR(sqltypes.CHAR):
+    render_bind_cast = True
+
+
+class _AsyncpgRange(ranges.AbstractSingleRangeImpl):
+    def bind_processor(self, dialect):
+        asyncpg_Range = dialect.dbapi.asyncpg.Range
+
+        def to_range(value):
+            if isinstance(value, ranges.Range):
+                value = asyncpg_Range(
+                    value.lower,
+                    value.upper,
+                    lower_inc=value.bounds[0] == "[",
+                    upper_inc=value.bounds[1] == "]",
+                    empty=value.empty,
+                )
+            return value
+
+        return to_range
+
+    def result_processor(self, dialect, coltype):
+        def to_range(value):
+            if value is not None:
+                empty = value.isempty
+                value = ranges.Range(
+                    value.lower,
+                    value.upper,
+                    bounds=f"{'[' if empty or value.lower_inc else '('}"  # type: ignore  # noqa: E501
+                    f"{']' if not empty and value.upper_inc else ')'}",
+                    empty=empty,
+                )
+            return value
+
+        return to_range
+
+
+class _AsyncpgMultiRange(ranges.AbstractMultiRangeImpl):
+    def bind_processor(self, dialect):
+        asyncpg_Range = dialect.dbapi.asyncpg.Range
+
+        NoneType = type(None)
+
+        def to_range(value):
+            if isinstance(value, (str, NoneType)):
+                return value
+
+            def to_range(value):
+                if isinstance(value, ranges.Range):
+                    value = asyncpg_Range(
+                        value.lower,
+                        value.upper,
+                        lower_inc=value.bounds[0] == "[",
+                        upper_inc=value.bounds[1] == "]",
+                        empty=value.empty,
+                    )
+                return value
+
+            return [to_range(element) for element in value]
+
+        return to_range
+
+    def result_processor(self, dialect, coltype):
+        def to_range_array(value):
+            def to_range(rvalue):
+                if rvalue is not None:
+                    empty = rvalue.isempty
+                    rvalue = ranges.Range(
+                        rvalue.lower,
+                        rvalue.upper,
+                        bounds=f"{'[' if empty or rvalue.lower_inc else '('}"  # type: ignore  # noqa: E501
+                        f"{']' if not empty and rvalue.upper_inc else ')'}",
+                        empty=empty,
+                    )
+                return rvalue
+
+            if value is not None:
+                value = ranges.MultiRange(to_range(elem) for elem in value)
+
+            return value
+
+        return to_range_array
+
+
+class PGExecutionContext_asyncpg(PGExecutionContext):
+    def handle_dbapi_exception(self, e):
+        if isinstance(
+            e,
+            (
+                self.dialect.dbapi.InvalidCachedStatementError,
+                self.dialect.dbapi.InternalServerError,
+            ),
+        ):
+            self.dialect._invalidate_schema_cache()
+
+    def pre_exec(self):
+        if self.isddl:
+            self.dialect._invalidate_schema_cache()
+
+        self.cursor._invalidate_schema_cache_asof = (
+            self.dialect._invalidate_schema_cache_asof
+        )
+
+        if not self.compiled:
+            return
+
+    def create_server_side_cursor(self):
+        return self._dbapi_connection.cursor(server_side=True)
+
+
+class PGCompiler_asyncpg(PGCompiler):
+    pass
+
+
+class PGIdentifierPreparer_asyncpg(PGIdentifierPreparer):
+    pass
+
+
+class AsyncAdapt_asyncpg_cursor:
+    __slots__ = (
+        "_adapt_connection",
+        "_connection",
+        "_rows",
+        "description",
+        "arraysize",
+        "rowcount",
+        "_cursor",
+        "_invalidate_schema_cache_asof",
+    )
+
+    server_side = False
+
+    def __init__(self, adapt_connection):
+        self._adapt_connection = adapt_connection
+        self._connection = adapt_connection._connection
+        self._rows = []
+        self._cursor = None
+        self.description = None
+        self.arraysize = 1
+        self.rowcount = -1
+        self._invalidate_schema_cache_asof = 0
+
+    def close(self):
+        self._rows[:] = []
+
+    def _handle_exception(self, error):
+        self._adapt_connection._handle_exception(error)
+
+    async def _prepare_and_execute(self, operation, parameters):
+        adapt_connection = self._adapt_connection
+
+        async with adapt_connection._execute_mutex:
+            if not adapt_connection._started:
+                await adapt_connection._start_transaction()
+
+            if parameters is None:
+                parameters = ()
+
+            try:
+                prepared_stmt, attributes = await adapt_connection._prepare(
+                    operation, self._invalidate_schema_cache_asof
+                )
+
+                if attributes:
+                    self.description = [
+                        (
+                            attr.name,
+                            attr.type.oid,
+                            None,
+                            None,
+                            None,
+                            None,
+                            None,
+                        )
+                        for attr in attributes
+                    ]
+                else:
+                    self.description = None
+
+                if self.server_side:
+                    self._cursor = await prepared_stmt.cursor(*parameters)
+                    self.rowcount = -1
+                else:
+                    self._rows = await prepared_stmt.fetch(*parameters)
+                    status = prepared_stmt.get_statusmsg()
+
+                    reg = re.match(
+                        r"(?:SELECT|UPDATE|DELETE|INSERT \d+) (\d+)", status
+                    )
+                    if reg:
+                        self.rowcount = int(reg.group(1))
+                    else:
+                        self.rowcount = -1
+
+            except Exception as error:
+                self._handle_exception(error)
+
+    async def _executemany(self, operation, seq_of_parameters):
+        adapt_connection = self._adapt_connection
+
+        self.description = None
+        async with adapt_connection._execute_mutex:
+            await adapt_connection._check_type_cache_invalidation(
+                self._invalidate_schema_cache_asof
+            )
+
+            if not adapt_connection._started:
+                await adapt_connection._start_transaction()
+
+            try:
+                return await self._connection.executemany(
+                    operation, seq_of_parameters
+                )
+            except Exception as error:
+                self._handle_exception(error)
+
+    def execute(self, operation, parameters=None):
+        self._adapt_connection.await_(
+            self._prepare_and_execute(operation, parameters)
+        )
+
+    def executemany(self, operation, seq_of_parameters):
+        return self._adapt_connection.await_(
+            self._executemany(operation, seq_of_parameters)
+        )
+
+    def setinputsizes(self, *inputsizes):
+        raise NotImplementedError()
+
+    def __iter__(self):
+        while self._rows:
+            yield self._rows.pop(0)
+
+    def fetchone(self):
+        if self._rows:
+            return self._rows.pop(0)
+        else:
+            return None
+
+    def fetchmany(self, size=None):
+        if size is None:
+            size = self.arraysize
+
+        retval = self._rows[0:size]
+        self._rows[:] = self._rows[size:]
+        return retval
+
+    def fetchall(self):
+        retval = self._rows[:]
+        self._rows[:] = []
+        return retval
+
+
+class AsyncAdapt_asyncpg_ss_cursor(AsyncAdapt_asyncpg_cursor):
+    server_side = True
+    __slots__ = ("_rowbuffer",)
+
+    def __init__(self, adapt_connection):
+        super().__init__(adapt_connection)
+        self._rowbuffer = None
+
+    def close(self):
+        self._cursor = None
+        self._rowbuffer = None
+
+    def _buffer_rows(self):
+        new_rows = self._adapt_connection.await_(self._cursor.fetch(50))
+        self._rowbuffer = collections.deque(new_rows)
+
+    def __aiter__(self):
+        return self
+
+    async def __anext__(self):
+        if not self._rowbuffer:
+            self._buffer_rows()
+
+        while True:
+            while self._rowbuffer:
+                yield self._rowbuffer.popleft()
+
+            self._buffer_rows()
+            if not self._rowbuffer:
+                break
+
+    def fetchone(self):
+        if not self._rowbuffer:
+            self._buffer_rows()
+            if not self._rowbuffer:
+                return None
+        return self._rowbuffer.popleft()
+
+    def fetchmany(self, size=None):
+        if size is None:
+            return self.fetchall()
+
+        if not self._rowbuffer:
+            self._buffer_rows()
+
+        buf = list(self._rowbuffer)
+        lb = len(buf)
+        if size > lb:
+            buf.extend(
+                self._adapt_connection.await_(self._cursor.fetch(size - lb))
+            )
+
+        result = buf[0:size]
+        self._rowbuffer = collections.deque(buf[size:])
+        return result
+
+    def fetchall(self):
+        ret = list(self._rowbuffer) + list(
+            self._adapt_connection.await_(self._all())
+        )
+        self._rowbuffer.clear()
+        return ret
+
+    async def _all(self):
+        rows = []
+
+        # TODO: looks like we have to hand-roll some kind of batching here.
+        # hardcoding for the moment but this should be improved.
+        while True:
+            batch = await self._cursor.fetch(1000)
+            if batch:
+                rows.extend(batch)
+                continue
+            else:
+                break
+        return rows
+
+    def executemany(self, operation, seq_of_parameters):
+        raise NotImplementedError(
+            "server side cursor doesn't support executemany yet"
+        )
+
+
+class AsyncAdapt_asyncpg_connection(AdaptedConnection):
+    __slots__ = (
+        "dbapi",
+        "isolation_level",
+        "_isolation_setting",
+        "readonly",
+        "deferrable",
+        "_transaction",
+        "_started",
+        "_prepared_statement_cache",
+        "_prepared_statement_name_func",
+        "_invalidate_schema_cache_asof",
+        "_execute_mutex",
+    )
+
+    await_ = staticmethod(await_only)
+
+    def __init__(
+        self,
+        dbapi,
+        connection,
+        prepared_statement_cache_size=100,
+        prepared_statement_name_func=None,
+    ):
+        self.dbapi = dbapi
+        self._connection = connection
+        self.isolation_level = self._isolation_setting = "read_committed"
+        self.readonly = False
+        self.deferrable = False
+        self._transaction = None
+        self._started = False
+        self._invalidate_schema_cache_asof = time.time()
+        self._execute_mutex = asyncio.Lock()
+
+        if prepared_statement_cache_size:
+            self._prepared_statement_cache = util.LRUCache(
+                prepared_statement_cache_size
+            )
+        else:
+            self._prepared_statement_cache = None
+
+        if prepared_statement_name_func:
+            self._prepared_statement_name_func = prepared_statement_name_func
+        else:
+            self._prepared_statement_name_func = self._default_name_func
+
+    async def _check_type_cache_invalidation(self, invalidate_timestamp):
+        if invalidate_timestamp > self._invalidate_schema_cache_asof:
+            await self._connection.reload_schema_state()
+            self._invalidate_schema_cache_asof = invalidate_timestamp
+
+    async def _prepare(self, operation, invalidate_timestamp):
+        await self._check_type_cache_invalidation(invalidate_timestamp)
+
+        cache = self._prepared_statement_cache
+        if cache is None:
+            prepared_stmt = await self._connection.prepare(
+                operation, name=self._prepared_statement_name_func()
+            )
+            attributes = prepared_stmt.get_attributes()
+            return prepared_stmt, attributes
+
+        # asyncpg uses a type cache for the "attributes" which seems to go
+        # stale independently of the PreparedStatement itself, so place that
+        # collection in the cache as well.
+        if operation in cache:
+            prepared_stmt, attributes, cached_timestamp = cache[operation]
+
+            # preparedstatements themselves also go stale for certain DDL
+            # changes such as size of a VARCHAR changing, so there is also
+            # a cross-connection invalidation timestamp
+            if cached_timestamp > invalidate_timestamp:
+                return prepared_stmt, attributes
+
+        prepared_stmt = await self._connection.prepare(
+            operation, name=self._prepared_statement_name_func()
+        )
+        attributes = prepared_stmt.get_attributes()
+        cache[operation] = (prepared_stmt, attributes, time.time())
+
+        return prepared_stmt, attributes
+
+    def _handle_exception(self, error):
+        if self._connection.is_closed():
+            self._transaction = None
+            self._started = False
+
+        if not isinstance(error, AsyncAdapt_asyncpg_dbapi.Error):
+            exception_mapping = self.dbapi._asyncpg_error_translate
+
+            for super_ in type(error).__mro__:
+                if super_ in exception_mapping:
+                    translated_error = exception_mapping[super_](
+                        "%s: %s" % (type(error), error)
+                    )
+                    translated_error.pgcode = translated_error.sqlstate = (
+                        getattr(error, "sqlstate", None)
+                    )
+                    raise translated_error from error
+            else:
+                raise error
+        else:
+            raise error
+
+    @property
+    def autocommit(self):
+        return self.isolation_level == "autocommit"
+
+    @autocommit.setter
+    def autocommit(self, value):
+        if value:
+            self.isolation_level = "autocommit"
+        else:
+            self.isolation_level = self._isolation_setting
+
+    def ping(self):
+        try:
+            _ = self.await_(self._async_ping())
+        except Exception as error:
+            self._handle_exception(error)
+
+    async def _async_ping(self):
+        if self._transaction is None and self.isolation_level != "autocommit":
+            # create a tranasction explicitly to support pgbouncer
+            # transaction mode.   See #10226
+            tr = self._connection.transaction()
+            await tr.start()
+            try:
+                await self._connection.fetchrow(";")
+            finally:
+                await tr.rollback()
+        else:
+            await self._connection.fetchrow(";")
+
+    def set_isolation_level(self, level):
+        if self._started:
+            self.rollback()
+        self.isolation_level = self._isolation_setting = level
+
+    async def _start_transaction(self):
+        if self.isolation_level == "autocommit":
+            return
+
+        try:
+            self._transaction = self._connection.transaction(
+                isolation=self.isolation_level,
+                readonly=self.readonly,
+                deferrable=self.deferrable,
+            )
+            await self._transaction.start()
+        except Exception as error:
+            self._handle_exception(error)
+        else:
+            self._started = True
+
+    def cursor(self, server_side=False):
+        if server_side:
+            return AsyncAdapt_asyncpg_ss_cursor(self)
+        else:
+            return AsyncAdapt_asyncpg_cursor(self)
+
+    def rollback(self):
+        if self._started:
+            try:
+                self.await_(self._transaction.rollback())
+            except Exception as error:
+                self._handle_exception(error)
+            finally:
+                self._transaction = None
+                self._started = False
+
+    def commit(self):
+        if self._started:
+            try:
+                self.await_(self._transaction.commit())
+            except Exception as error:
+                self._handle_exception(error)
+            finally:
+                self._transaction = None
+                self._started = False
+
+    def close(self):
+        self.rollback()
+
+        self.await_(self._connection.close())
+
+    def terminate(self):
+        if util.concurrency.in_greenlet():
+            # in a greenlet; this is the connection was invalidated
+            # case.
+            try:
+                # try to gracefully close; see #10717
+                # timeout added in asyncpg 0.14.0 December 2017
+                self.await_(self._connection.close(timeout=2))
+            except (
+                asyncio.TimeoutError,
+                OSError,
+                self.dbapi.asyncpg.PostgresError,
+            ):
+                # in the case where we are recycling an old connection
+                # that may have already been disconnected, close() will
+                # fail with the above timeout.  in this case, terminate
+                # the connection without any further waiting.
+                # see issue #8419
+                self._connection.terminate()
+        else:
+            # not in a greenlet; this is the gc cleanup case
+            self._connection.terminate()
+        self._started = False
+
+    @staticmethod
+    def _default_name_func():
+        return None
+
+
+class AsyncAdaptFallback_asyncpg_connection(AsyncAdapt_asyncpg_connection):
+    __slots__ = ()
+
+    await_ = staticmethod(await_fallback)
+
+
+class AsyncAdapt_asyncpg_dbapi:
+    def __init__(self, asyncpg):
+        self.asyncpg = asyncpg
+        self.paramstyle = "numeric_dollar"
+
+    def connect(self, *arg, **kw):
+        async_fallback = kw.pop("async_fallback", False)
+        creator_fn = kw.pop("async_creator_fn", self.asyncpg.connect)
+        prepared_statement_cache_size = kw.pop(
+            "prepared_statement_cache_size", 100
+        )
+        prepared_statement_name_func = kw.pop(
+            "prepared_statement_name_func", None
+        )
+
+        if util.asbool(async_fallback):
+            return AsyncAdaptFallback_asyncpg_connection(
+                self,
+                await_fallback(creator_fn(*arg, **kw)),
+                prepared_statement_cache_size=prepared_statement_cache_size,
+                prepared_statement_name_func=prepared_statement_name_func,
+            )
+        else:
+            return AsyncAdapt_asyncpg_connection(
+                self,
+                await_only(creator_fn(*arg, **kw)),
+                prepared_statement_cache_size=prepared_statement_cache_size,
+                prepared_statement_name_func=prepared_statement_name_func,
+            )
+
+    class Error(Exception):
+        pass
+
+    class Warning(Exception):  # noqa
+        pass
+
+    class InterfaceError(Error):
+        pass
+
+    class DatabaseError(Error):
+        pass
+
+    class InternalError(DatabaseError):
+        pass
+
+    class OperationalError(DatabaseError):
+        pass
+
+    class ProgrammingError(DatabaseError):
+        pass
+
+    class IntegrityError(DatabaseError):
+        pass
+
+    class DataError(DatabaseError):
+        pass
+
+    class NotSupportedError(DatabaseError):
+        pass
+
+    class InternalServerError(InternalError):
+        pass
+
+    class InvalidCachedStatementError(NotSupportedError):
+        def __init__(self, message):
+            super().__init__(
+                message + " (SQLAlchemy asyncpg dialect will now invalidate "
+                "all prepared caches in response to this exception)",
+            )
+
+    # pep-249 datatype placeholders.  As of SQLAlchemy 2.0 these aren't
+    # used, however the test suite looks for these in a few cases.
+    STRING = util.symbol("STRING")
+    NUMBER = util.symbol("NUMBER")
+    DATETIME = util.symbol("DATETIME")
+
+    @util.memoized_property
+    def _asyncpg_error_translate(self):
+        import asyncpg
+
+        return {
+            asyncpg.exceptions.IntegrityConstraintViolationError: self.IntegrityError,  # noqa: E501
+            asyncpg.exceptions.PostgresError: self.Error,
+            asyncpg.exceptions.SyntaxOrAccessError: self.ProgrammingError,
+            asyncpg.exceptions.InterfaceError: self.InterfaceError,
+            asyncpg.exceptions.InvalidCachedStatementError: self.InvalidCachedStatementError,  # noqa: E501
+            asyncpg.exceptions.InternalServerError: self.InternalServerError,
+        }
+
+    def Binary(self, value):
+        return value
+
+
+class PGDialect_asyncpg(PGDialect):
+    driver = "asyncpg"
+    supports_statement_cache = True
+
+    supports_server_side_cursors = True
+
+    render_bind_cast = True
+    has_terminate = True
+
+    default_paramstyle = "numeric_dollar"
+    supports_sane_multi_rowcount = False
+    execution_ctx_cls = PGExecutionContext_asyncpg
+    statement_compiler = PGCompiler_asyncpg
+    preparer = PGIdentifierPreparer_asyncpg
+
+    colspecs = util.update_copy(
+        PGDialect.colspecs,
+        {
+            sqltypes.String: AsyncpgString,
+            sqltypes.ARRAY: AsyncpgARRAY,
+            BIT: AsyncpgBit,
+            CITEXT: CITEXT,
+            REGCONFIG: AsyncpgREGCONFIG,
+            sqltypes.Time: AsyncpgTime,
+            sqltypes.Date: AsyncpgDate,
+            sqltypes.DateTime: AsyncpgDateTime,
+            sqltypes.Interval: AsyncPgInterval,
+            INTERVAL: AsyncPgInterval,
+            sqltypes.Boolean: AsyncpgBoolean,
+            sqltypes.Integer: AsyncpgInteger,
+            sqltypes.BigInteger: AsyncpgBigInteger,
+            sqltypes.Numeric: AsyncpgNumeric,
+            sqltypes.Float: AsyncpgFloat,
+            sqltypes.JSON: AsyncpgJSON,
+            sqltypes.LargeBinary: AsyncpgByteA,
+            json.JSONB: AsyncpgJSONB,
+            sqltypes.JSON.JSONPathType: AsyncpgJSONPathType,
+            sqltypes.JSON.JSONIndexType: AsyncpgJSONIndexType,
+            sqltypes.JSON.JSONIntIndexType: AsyncpgJSONIntIndexType,
+            sqltypes.JSON.JSONStrIndexType: AsyncpgJSONStrIndexType,
+            sqltypes.Enum: AsyncPgEnum,
+            OID: AsyncpgOID,
+            REGCLASS: AsyncpgREGCLASS,
+            sqltypes.CHAR: AsyncpgCHAR,
+            ranges.AbstractSingleRange: _AsyncpgRange,
+            ranges.AbstractMultiRange: _AsyncpgMultiRange,
+        },
+    )
+    is_async = True
+    _invalidate_schema_cache_asof = 0
+
+    def _invalidate_schema_cache(self):
+        self._invalidate_schema_cache_asof = time.time()
+
+    @util.memoized_property
+    def _dbapi_version(self):
+        if self.dbapi and hasattr(self.dbapi, "__version__"):
+            return tuple(
+                [
+                    int(x)
+                    for x in re.findall(
+                        r"(\d+)(?:[-\.]?|$)", self.dbapi.__version__
+                    )
+                ]
+            )
+        else:
+            return (99, 99, 99)
+
+    @classmethod
+    def import_dbapi(cls):
+        return AsyncAdapt_asyncpg_dbapi(__import__("asyncpg"))
+
+    @util.memoized_property
+    def _isolation_lookup(self):
+        return {
+            "AUTOCOMMIT": "autocommit",
+            "READ COMMITTED": "read_committed",
+            "REPEATABLE READ": "repeatable_read",
+            "SERIALIZABLE": "serializable",
+        }
+
+    def get_isolation_level_values(self, dbapi_connection):
+        return list(self._isolation_lookup)
+
+    def set_isolation_level(self, dbapi_connection, level):
+        dbapi_connection.set_isolation_level(self._isolation_lookup[level])
+
+    def set_readonly(self, connection, value):
+        connection.readonly = value
+
+    def get_readonly(self, connection):
+        return connection.readonly
+
+    def set_deferrable(self, connection, value):
+        connection.deferrable = value
+
+    def get_deferrable(self, connection):
+        return connection.deferrable
+
+    def do_terminate(self, dbapi_connection) -> None:
+        dbapi_connection.terminate()
+
+    def create_connect_args(self, url):
+        opts = url.translate_connect_args(username="user")
+        multihosts, multiports = self._split_multihost_from_url(url)
+
+        opts.update(url.query)
+
+        if multihosts:
+            assert multiports
+            if len(multihosts) == 1:
+                opts["host"] = multihosts[0]
+                if multiports[0] is not None:
+                    opts["port"] = multiports[0]
+            elif not all(multihosts):
+                raise exc.ArgumentError(
+                    "All hosts are required to be present"
+                    " for asyncpg multiple host URL"
+                )
+            elif not all(multiports):
+                raise exc.ArgumentError(
+                    "All ports are required to be present"
+                    " for asyncpg multiple host URL"
+                )
+            else:
+                opts["host"] = list(multihosts)
+                opts["port"] = list(multiports)
+        else:
+            util.coerce_kw_type(opts, "port", int)
+        util.coerce_kw_type(opts, "prepared_statement_cache_size", int)
+        return ([], opts)
+
+    def do_ping(self, dbapi_connection):
+        dbapi_connection.ping()
+        return True
+
+    @classmethod
+    def get_pool_class(cls, url):
+        async_fallback = url.query.get("async_fallback", False)
+
+        if util.asbool(async_fallback):
+            return pool.FallbackAsyncAdaptedQueuePool
+        else:
+            return pool.AsyncAdaptedQueuePool
+
+    def is_disconnect(self, e, connection, cursor):
+        if connection:
+            return connection._connection.is_closed()
+        else:
+            return isinstance(
+                e, self.dbapi.InterfaceError
+            ) and "connection is closed" in str(e)
+
+    async def setup_asyncpg_json_codec(self, conn):
+        """set up JSON codec for asyncpg.
+
+        This occurs for all new connections and
+        can be overridden by third party dialects.
+
+        .. versionadded:: 1.4.27
+
+        """
+
+        asyncpg_connection = conn._connection
+        deserializer = self._json_deserializer or _py_json.loads
+
+        def _json_decoder(bin_value):
+            return deserializer(bin_value.decode())
+
+        await asyncpg_connection.set_type_codec(
+            "json",
+            encoder=str.encode,
+            decoder=_json_decoder,
+            schema="pg_catalog",
+            format="binary",
+        )
+
+    async def setup_asyncpg_jsonb_codec(self, conn):
+        """set up JSONB codec for asyncpg.
+
+        This occurs for all new connections and
+        can be overridden by third party dialects.
+
+        .. versionadded:: 1.4.27
+
+        """
+
+        asyncpg_connection = conn._connection
+        deserializer = self._json_deserializer or _py_json.loads
+
+        def _jsonb_encoder(str_value):
+            # \x01 is the prefix for jsonb used by PostgreSQL.
+            # asyncpg requires it when format='binary'
+            return b"\x01" + str_value.encode()
+
+        deserializer = self._json_deserializer or _py_json.loads
+
+        def _jsonb_decoder(bin_value):
+            # the byte is the \x01 prefix for jsonb used by PostgreSQL.
+            # asyncpg returns it when format='binary'
+            return deserializer(bin_value[1:].decode())
+
+        await asyncpg_connection.set_type_codec(
+            "jsonb",
+            encoder=_jsonb_encoder,
+            decoder=_jsonb_decoder,
+            schema="pg_catalog",
+            format="binary",
+        )
+
+    async def _disable_asyncpg_inet_codecs(self, conn):
+        asyncpg_connection = conn._connection
+
+        await asyncpg_connection.set_type_codec(
+            "inet",
+            encoder=lambda s: s,
+            decoder=lambda s: s,
+            schema="pg_catalog",
+            format="text",
+        )
+
+        await asyncpg_connection.set_type_codec(
+            "cidr",
+            encoder=lambda s: s,
+            decoder=lambda s: s,
+            schema="pg_catalog",
+            format="text",
+        )
+
+    def on_connect(self):
+        """on_connect for asyncpg
+
+        A major component of this for asyncpg is to set up type decoders at the
+        asyncpg level.
+
+        See https://github.com/MagicStack/asyncpg/issues/623 for
+        notes on JSON/JSONB implementation.
+
+        """
+
+        super_connect = super().on_connect()
+
+        def connect(conn):
+            conn.await_(self.setup_asyncpg_json_codec(conn))
+            conn.await_(self.setup_asyncpg_jsonb_codec(conn))
+
+            if self._native_inet_types is False:
+                conn.await_(self._disable_asyncpg_inet_codecs(conn))
+            if super_connect is not None:
+                super_connect(conn)
+
+        return connect
+
+    def get_driver_connection(self, connection):
+        return connection._connection
+
+
+dialect = PGDialect_asyncpg