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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 unixtimestamp(datetime):
 """Get unix time stamp from that given datetime. If datetime is not tzaware then it's assumed that it is UTC """

    epoch = UTC.localize(datetime.utcfromtimestamp(0))
    if not datetime.tzinfo:
        dt = UTC.localize(datetime)
    else:
        dt = UTC.normalize(datetime)
    delta = dt - epoch
    return total_seconds(delta)