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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 PopAttributeContainer(self):
 """Pops a serialized attribute container from the list. Returns: bytes: serialized attribute container data. """

    try:
      serialized_data = self._list.pop(0)
      self.data_size -= len(serialized_data)
      return serialized_data

    except IndexError:
      return None