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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 timestamp(dt):
 	""" 	Return POSIX timestamp as float. 	True 	True 	"""

	if dt.tzinfo is None:
		return time.mktime((
			dt.year, dt.month, dt.day,
			dt.hour, dt.minute, dt.second,
			-1, -1, -1)) + dt.microsecond / 1e6
	else:
		return (dt - _EPOCH).total_seconds()