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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 invoke(self):
 """ Run callback, optionally passing a variable number of arguments `callback_args` """


        # Don't sleep a hook if it has never run
        if self.timeout_milliseconds > 0:
            self.ready_time = (
                datetime.now() +
                timedelta(milliseconds=self.timeout_milliseconds))

        self.callback(self.callback_args)