@classmethod<EOL><INDENT>def get_connection_pool(self, pool_id, *args, **kwargs):<DEDENT>
assert isinstance(pool_id, (str, unicode))<EOL>if not hasattr(self, '<STR_LIT>'):<EOL><INDENT>self._pools = {}<EOL><DEDENT>if pool_id not in self._pools:<EOL><INDENT>self._pools[pool_id] = ConnectionPool(*args, **kwargs)<EOL><DEDENT>return self._pools[pool_id]<EOL>
get a connection pool, transparently creating it if it doesn't already exist

        :Parameters:
            - `pool_id`: unique id for a connection pool