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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 _start(self):
        ''' mark the time of execution for duration calculations later '''
        self.start = time.time()
        self.result['start'] = str(datetime.datetime.now())
        if not self.pause_type == 'prompt':
            print "(^C-c = continue early, ^C-a = abort)"