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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_child_edge(cls, index, left_parent, right_parent):
 """Construct a child edge from two parent edges."""

        [ed1, ed2, depend_set] = cls._identify_eds_ing(left_parent, right_parent)
        left_u, right_u = cls.get_conditional_uni(left_parent, right_parent)
        X = np.array([[x, y] for x, y in zip(left_u, right_u)])
        name, theta = Bivariate.select_copula(X)
        new_edge = Edge(index, ed1, ed2, name, theta)
        new_edge.D = depend_set
        new_edge.parents = [left_parent, right_parent]
        return new_edge