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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 get_max_num_classes(self):
 """Compute the maximum number of classes any subtask has. This is useful for modifying the size of the softmax to include the output labels for the classification tasks. Currently, labels from different tasks are overloaded. Returns: num: Highest number of output classes in any text classification sub-task within this MultiProblem. """

    num = 0
    for task in self.task_list:
      if hasattr(task, "num_classes"):
        if num < task.num_classes:
          num = task.num_classes

    return num