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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 async def release(self, connection, *, timeout=None):
 """Release a database connection back to the pool. :param Connection connection: A :class:`~asyncpg.connection.Connection` object to release. :param float timeout: A timeout for releasing the connection. If not specified, defaults to the timeout provided in the corresponding call to the :meth:`Pool.acquire() <asyncpg.pool.Pool.acquire>` method. .. versionchanged:: 0.14.0 Added the *timeout* parameter. """

        if (type(connection) is not PoolConnectionProxy or
                connection._holder._pool is not self):
            raise exceptions.InterfaceError(
                'Pool.release() received invalid connection: '
                '{connection!r} is not a member of this pool'.format(
                    connection=connection))

        if connection._con is None:
            # Already released, do nothing.
            return

        self._check_init()

        # Let the connection do its internal housekeeping when its released.
        connection._con._on_release()

        ch = connection._holder
        if timeout is None:
            timeout = ch._timeout

        # Use asyncio.shield() to guarantee that task cancellation
        # does not prevent the connection from being returned to the
        # pool properly.
        return await asyncio.shield(ch.release(timeout), loop=self._loop)