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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 increment_lessons(self, measure_vals, reward_buff_sizes=None):
 """Attempts to increments all the lessons of all the curriculums in this MetaCurriculum. Note that calling this method does not guarantee the lesson of a curriculum will increment. The lesson of a curriculum will only increment if the specified measure threshold defined in the curriculum has been reached and the minimum number of episodes in the lesson have been completed. Args: measure_vals (dict):
 A dict of brain name to measure value. reward_buff_sizes (dict):
 A dict of brain names to the size of their corresponding reward buffers. Returns: A dict from brain name to whether that brain's lesson number was incremented. """

        ret = {}
        if reward_buff_sizes:
            for brain_name, buff_size in reward_buff_sizes.items():
                if self._lesson_ready_to_increment(brain_name, buff_size):
                    measure_val = measure_vals[brain_name]
                    ret[brain_name] = (self.brains_to_curriculums[brain_name]
                                           .increment_lesson(measure_val))
        else:
            for brain_name, measure_val in measure_vals.items():
                ret[brain_name] = (self.brains_to_curriculums[brain_name]
                                       .increment_lesson(measure_val))
        return ret