code: def unpack_systemtime(self, offset):
          
          o = self._offset + offset
          try:
              parts = struct.unpack_from("<HHHHHHHH", self._buf, o)
          except struct.error:
              raise OverrunBufferException(o, len(self._buf))
          return datetime(parts[0], parts[1],
                          parts[3],  # skip part 2 (day of week)
                          parts[4], parts[5],
                          parts[6], parts[7])
docs: Returns a datetime from the QWORD Windows SYSTEMTIME timestamp
            starting at the relative offset.
            See http://msdn.microsoft.com/en-us/library/ms724950%28VS.85%29.aspx
          Arguments:
          - `offset`: The relative offset from the start of the block.
          Throws:
          - `OverrunBufferException`