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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 WriteTaskCompletion(self, aborted=False):
 """Writes task completion information. Args: aborted (Optional[bool]):
 True if the session was aborted. Raises: IOError: if the storage type is not supported or when the storage writer is closed. OSError: if the storage type is not supported or when the storage writer is closed. """

    self._RaiseIfNotWritable()

    if self._storage_type != definitions.STORAGE_TYPE_TASK:
      raise IOError('Unsupported storage type.')

    self._task.aborted = aborted
    task_completion = self._task.CreateTaskCompletion()
    self._storage_file.WriteTaskCompletion(task_completion)