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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(x):
 """Get a timestamp from a date in python 3 and python 2"""

    if x.tzinfo is None:
        # Naive dates to utc
        x = x.replace(tzinfo=utc)

    if hasattr(x, 'timestamp'):
        return x.timestamp()
    else:
        return (x - datetime(1970, 1, 1, tzinfo=utc)).total_seconds()