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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 _set_time(self, m):
        '''set time for a message'''
        # really just left here for profiling
        m._timestamp = self.timestamp
        if len(m._fieldnames) > 0 and self.clock is not None:
            self.clock.set_message_timestamp(m)