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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 _validate_jpx_box_sequence(self, boxes):
 """Run through series of tests for JPX box legality."""

        self._validate_label(boxes)
        self._validate_jpx_compatibility(boxes, boxes[1].compatibility_list)
        self._validate_singletons(boxes)
        self._validate_top_level(boxes)