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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 IsAllocated(self):
 """Determines if the file entry is allocated. Returns: bool: True if the file entry is allocated. """

    if self._stat_object is None:
      self._stat_object = self._GetStat()
    return self._stat_object and self._stat_object.is_allocated