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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 _generate_edges(self, edge_prob):
 """Generate a random tree-structured dependency graph based on a specified edge probability. Also create helper data struct mapping child -> parent. """

        self.E, self.parent = [], {}
        for i in range(self.m):
            if random() < edge_prob and i > 0:
                p_i = choice(i)
                self.E.append((p_i, i))
                self.parent[i] = p_i