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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 chk_edges_nodes(edges, nodes, name):
 """Check that user specified edges have a node which exists."""

        edge_nodes = set(e for es in edges for e in es)
        missing_nodes = edge_nodes.difference(nodes)
        assert not missing_nodes, "MISSING: {GOs}\n{NM} EDGES MISSING {N} NODES (OF {T})".format(
            NM=name, N=len(missing_nodes), T=len(edge_nodes), GOs=missing_nodes)