import datetime as dt

NANOSECONDS_PER_MICROSECOND = 1000

MICROSECONDS_PER_MILLISECOND = 1000
NANOSECONDS_PER_MILLISECOND = 1000000  

MILLISECONDS_PER_SECOND = 1000
MICROSECONDS_PER_SECOND = 1000000
NANOSECONDS_PER_SECOND = 1000000000    

SECONDS_PER_MINUTE = 60
MILLISECONDS_PER_MINUTE = 60000
MICROSECONDS_PER_MINUTE = 60000000
NANOSECONDS_PER_MINUTE = 60000000000

MINUTES_PER_HOUR = 60
SECONDS_PER_HOUR = 3600
MILLISECONDS_PER_HOUR = 3600000
MICROSECONDS_PER_HOUR = 3600000000
NANOSECONDS_PER_HOUR = 3600000000000

HOURS_PER_DAY = 24
MINUTES_PER_DAY = 1440
SECONDS_PER_DAY = 86400
MILLISECONDS_PER_DAY = 86400000
MICROSECONDS_PER_DAY = 86400000000
NANOSECONDS_PER_DAY = 86400000000000

ONE_MICROSECOND = dt.timedelta(microseconds=1)
ONE_MILLISECOND = dt.timedelta(microseconds=1000)
ONE_SECOND = dt.timedelta(seconds=1)
ONE_MINUTE = dt.timedelta(minutes=1)
ONE_HOUR = dt.timedelta(hours=1)
ONE_DAY = dt.timedelta(days=1)

def _test():
    import doctest
    doctest.testmod(verbose=False)

if __name__ == '__main__':
    _test()
