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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:
 def remove_waiter(self, waiter_handle):
 """Remove a message callback. This call will remove a callback previously registered using every_match. Args: waiter_handle (object):
 The opaque handle returned by the previous call to every_match(). """


        spec, waiter = waiter_handle
        self._remove_waiter(spec, waiter)