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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 datetime64_to_datetime(dt):
 """ convert numpy's datetime64 to datetime """

    dt64 = np.datetime64(dt)
    ts = (dt64 - np.datetime64('1970-01-01T00:00:00')) / np.timedelta64(1, 's')
    return datetime.datetime.utcfromtimestamp(ts)