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diff --git a/lib/sqlalchemy/orm/scoping.py b/lib/sqlalchemy/orm/scoping.py
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+++ b/lib/sqlalchemy/orm/scoping.py
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+# orm/scoping.py
+# Copyright (C) 2005-2022 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
+
+from . import class_mapper
+from . import exc as orm_exc
+from .session import Session
+from .. import exc as sa_exc
+from ..util import create_proxy_methods
+from ..util import ScopedRegistry
+from ..util import ThreadLocalRegistry
+from ..util import warn
+from ..util import warn_deprecated
+
+__all__ = ["scoped_session", "ScopedSessionMixin"]
+
+
+class ScopedSessionMixin(object):
+    @property
+    def _proxied(self):
+        return self.registry()
+
+    def __call__(self, **kw):
+        r"""Return the current :class:`.Session`, creating it
+        using the :attr:`.scoped_session.session_factory` if not present.
+
+        :param \**kw: Keyword arguments will be passed to the
+         :attr:`.scoped_session.session_factory` callable, if an existing
+         :class:`.Session` is not present.  If the :class:`.Session` is present
+         and keyword arguments have been passed,
+         :exc:`~sqlalchemy.exc.InvalidRequestError` is raised.
+
+        """
+        if kw:
+            if self.registry.has():
+                raise sa_exc.InvalidRequestError(
+                    "Scoped session is already present; "
+                    "no new arguments may be specified."
+                )
+            else:
+                sess = self.session_factory(**kw)
+                self.registry.set(sess)
+        else:
+            sess = self.registry()
+        if not self._support_async and sess._is_asyncio:
+            warn_deprecated(
+                "Using `scoped_session` with asyncio is deprecated and "
+                "will raise an error in a future version. "
+                "Please use `async_scoped_session` instead.",
+                "1.4.23",
+            )
+        return sess
+
+    def configure(self, **kwargs):
+        """reconfigure the :class:`.sessionmaker` used by this
+        :class:`.scoped_session`.
+
+        See :meth:`.sessionmaker.configure`.
+
+        """
+
+        if self.registry.has():
+            warn(
+                "At least one scoped session is already present. "
+                " configure() can not affect sessions that have "
+                "already been created."
+            )
+
+        self.session_factory.configure(**kwargs)
+
+
+@create_proxy_methods(
+    Session,
+    ":class:`_orm.Session`",
+    ":class:`_orm.scoping.scoped_session`",
+    classmethods=["close_all", "object_session", "identity_key"],
+    methods=[
+        "__contains__",
+        "__iter__",
+        "add",
+        "add_all",
+        "begin",
+        "begin_nested",
+        "close",
+        "commit",
+        "connection",
+        "delete",
+        "execute",
+        "expire",
+        "expire_all",
+        "expunge",
+        "expunge_all",
+        "flush",
+        "get",
+        "get_bind",
+        "is_modified",
+        "bulk_save_objects",
+        "bulk_insert_mappings",
+        "bulk_update_mappings",
+        "merge",
+        "query",
+        "refresh",
+        "rollback",
+        "scalar",
+        "scalars",
+    ],
+    attributes=[
+        "bind",
+        "dirty",
+        "deleted",
+        "new",
+        "identity_map",
+        "is_active",
+        "autoflush",
+        "no_autoflush",
+        "info",
+        "autocommit",
+    ],
+)
+class scoped_session(ScopedSessionMixin):
+    """Provides scoped management of :class:`.Session` objects.
+
+    See :ref:`unitofwork_contextual` for a tutorial.
+
+    .. note::
+
+       When using :ref:`asyncio_toplevel`, the async-compatible
+       :class:`_asyncio.async_scoped_session` class should be
+       used in place of :class:`.scoped_session`.
+
+    """
+
+    _support_async = False
+
+    session_factory = None
+    """The `session_factory` provided to `__init__` is stored in this
+    attribute and may be accessed at a later time.  This can be useful when
+    a new non-scoped :class:`.Session` or :class:`_engine.Connection` to the
+    database is needed."""
+
+    def __init__(self, session_factory, scopefunc=None):
+        """Construct a new :class:`.scoped_session`.
+
+        :param session_factory: a factory to create new :class:`.Session`
+         instances. This is usually, but not necessarily, an instance
+         of :class:`.sessionmaker`.
+        :param scopefunc: optional function which defines
+         the current scope.   If not passed, the :class:`.scoped_session`
+         object assumes "thread-local" scope, and will use
+         a Python ``threading.local()`` in order to maintain the current
+         :class:`.Session`.  If passed, the function should return
+         a hashable token; this token will be used as the key in a
+         dictionary in order to store and retrieve the current
+         :class:`.Session`.
+
+        """
+        self.session_factory = session_factory
+
+        if scopefunc:
+            self.registry = ScopedRegistry(session_factory, scopefunc)
+        else:
+            self.registry = ThreadLocalRegistry(session_factory)
+
+    def remove(self):
+        """Dispose of the current :class:`.Session`, if present.
+
+        This will first call :meth:`.Session.close` method
+        on the current :class:`.Session`, which releases any existing
+        transactional/connection resources still being held; transactions
+        specifically are rolled back.  The :class:`.Session` is then
+        discarded.   Upon next usage within the same scope,
+        the :class:`.scoped_session` will produce a new
+        :class:`.Session` object.
+
+        """
+
+        if self.registry.has():
+            self.registry().close()
+        self.registry.clear()
+
+    def query_property(self, query_cls=None):
+        """return a class property which produces a :class:`_query.Query`
+        object
+        against the class and the current :class:`.Session` when called.
+
+        e.g.::
+
+            Session = scoped_session(sessionmaker())
+
+            class MyClass(object):
+                query = Session.query_property()
+
+            # after mappers are defined
+            result = MyClass.query.filter(MyClass.name=='foo').all()
+
+        Produces instances of the session's configured query class by
+        default.  To override and use a custom implementation, provide
+        a ``query_cls`` callable.  The callable will be invoked with
+        the class's mapper as a positional argument and a session
+        keyword argument.
+
+        There is no limit to the number of query properties placed on
+        a class.
+
+        """
+
+        class query(object):
+            def __get__(s, instance, owner):
+                try:
+                    mapper = class_mapper(owner)
+                    if mapper:
+                        if query_cls:
+                            # custom query class
+                            return query_cls(mapper, session=self.registry())
+                        else:
+                            # session's configured query class
+                            return self.registry().query(mapper)
+                except orm_exc.UnmappedClassError:
+                    return None
+
+        return query()
+
+
+ScopedSession = scoped_session
+"""Old name for backwards compatibility."""