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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 from_unix(cls, seconds, milliseconds=0):
 """ Produce a full |datetime.datetime| object from a Unix timestamp """

        base = list(time.gmtime(seconds))[0:6]
        base.append(milliseconds * 1000)  # microseconds
        return cls(*base)