ОШИБКА В PYTHON: TypeError: ufunc 'multiply' не содержит цикл с типами соответствия сигнатуры dtype ('

Question

Я запускаю этот код на python

with open("test.txt", "r") as networkFile:
    for line in networkFile:
            src = line.split()[0]
            nodes.append(src)
nodesf = np.unique(nodes)

with open("test.txt", "r") as networkFile:
    for line in networkFile:
            src = line.split()[0]
            network.append([src])
edgesf = np.array(network)

avgDegree = (2 * edgesf) / nodesf
print("avgDegree: ",avgDegree)

и выдаю мне ошибку в строке avgDegree = (2 * edgesf) / nodesf

TypeError: ufunc 'multiply' did not contain a loop with signature matching types   
`dtype('<U4') dtype('<U4') dtype('<U4')`

Есть идеи?