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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 time_stamp():
 """Setup time functions :returns: ``tuple`` """


    # Time constants
    fmt = '%Y-%m-%dT%H:%M:%S.%f'
    date = datetime.datetime
    date_delta = datetime.timedelta
    now = datetime.datetime.utcnow()

    return fmt, date, date_delta, now