ValueError：没有足够的值可解包（预期2，得到1）NetworkX python 3

错误报告

Python3.5.2\lib\site-packages\networkx\drawing\nx_pylab.py", 
line 836, in draw_networkx_edge_labels for (n1, n2), label in labels.items():
ValueError: not enough values to unpack (expected 2, got 1)    

map_paths_reduced =  [(0, 75), (75, 38), (38, 86), (86, 119), (119, 85), (85, 44), (44, 65), (65, 127), (127, 106), (106, 31)]
edge_labels_dict_reduced =  {'7': '27.0', '4': '31.0', '2': '17.0', '0': '12.0', '6': '13.0', '1': '16.0', '8': '8.0', '9': '34.0', '3': '6.0', '5': '45.0'}

其中len（edge_labels）= 150

G = nx.DiGraph()
G.add_nodes_from(range(len(edge_labels)+1))
black_edges = [edge for edge in G.edges()]
pos = nx.random_layout(G)
G.add_edges_from(map_paths_reduced)

nx.draw_networkx_nodes(G, pos, cmap=plt.get_cmap('jet'), node_size=100)
nx.draw_networkx_labels(G, pos, font_size=1)
nx.draw_networkx_edges(G, pos, edgelist=black_edges, arrows=True)
nx.draw_networkx_edge_labels(G, pos, edge_labels=edge_labels_dict_reduced) ##ERROR REPORTED HERE
nx.draw_networkx(G, pos, arrows=True)
return plt.show()

当我使用“ labels”参数而不是“ edge_labels”在nx.draw_networkx_edge_labels内部传递边缘标签字典时，它显示了空字典，如图所示。但是我正在寻找带有key：value条目的边缘标签。