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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 handle(self, operation, operation_name=None, sender_kwarg=None):
 """Handle an operation using the specified function @param operation: function to call for this operation @param operation_name: operation name. if unspecified operation.__name__ is used @param sender_kwarg: optional keyword arg on operation to feed in sender name """

        if not self._consumer:
            self._consumer = DashiConsumer(self, self._conn,
                    self._name, self._exchange, sysname=self._sysname)
        self._consumer.add_op(operation_name or operation.__name__, operation,
                              sender_kwarg=sender_kwarg)