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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 add_edge(edges, edge_points, coords, i, j):
 """ Add a line between the i-th and j-th points, if not in the list already """

    if (i, j) in edges or (j, i) in edges:
        # already added
        return( edges.add((i, j)), edge_points.append(coords[[i, j]]))