<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def call_later(self, delay, callback):
 """Schedule a one-shot timeout given delay seconds. This method is only useful for compatibility with older versions of pika. Args: delay (float):
 Non-negative number of seconds from now until expiration callback (method):
 The callback method, having the signature `callback()` """

        if hasattr(self._connection.ioloop, "call_later"):
            self._connection.ioloop.call_later(delay, callback)
        else:
            self._connection.ioloop.add_timeout(delay, callback)