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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_relation_cnt(self):
 """Return a Counter containing all relations contained in the Annotation Extensions."""

        ctr = cx.Counter()
        for ntgpad in self.associations:
            if ntgpad.Extension is not None:
                ctr += ntgpad.Extension.get_relations_cnt()
        return ctr