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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_vertices_from_edge_list(graph, edge_list):
 """Transforms a list of edges into a list of the nodes those edges connect. Returns a list of nodes, or an empty list if given an empty list. """

    node_set = set()
    for edge_id in edge_list:
        edge = graph.get_edge(edge_id)
        a, b = edge['vertices']
        node_set.add(a)
        node_set.add(b)

    return list(node_set)