'Return a "raw" DBAPI connection from the connection pool.
The returned object is a proxied version of the DBAPI
connection object used by the underlying driver in use.
The object will have all the same behavior as the real DBAPI
connection, except that its ``close()`` method will result in the
connection being returned to the pool, rather than being closed
for real.
This method provides direct DBAPI connection access for
special situations.  In most situations, the :class:`.Connection`
object should be used, which is procured using the
:meth:`.Engine.connect` method.'

def raw_connection(self):

    return self.pool.unique_connection()
