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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_c2ps(self):
 """Set child2parents dict for all parents used in this set of edges."""

        c2ps = defaultdict(set)
        for goid_child, goid_parent in self.edges:
            c2ps[goid_child].add(goid_parent)
        return c2ps