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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 _GetDateTime(self, filetime):
 """Retrieves the date and time from a FILETIME timestamp. Args: filetime (int):
 FILETIME timestamp. Returns: dfdatetime.DateTimeValues: date and time. """

    if filetime == 0:
      return dfdatetime_semantic_time.SemanticTime('Not set')

    return dfdatetime_filetime.Filetime(timestamp=filetime)