igraph密谋与cairo错误

Question

我正在尝试用python igraph创建一个情节：

from igraph import *

vertices = ["one", "two", "three"]
edges = [(0,2),(2,1),(0,1)]

g = Graph(vertex_attrs={"label": vertices}, edges=edges, directed=True)

plot(g)

我安装了所有这些：

sudo apt-get install libffi-dev
sudo pip install cffi
sudo pip install cairocffi

我仍然会收到此错误：

Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/home/chovanec/anaconda3/lib/python3.5/site-packages/igraph/drawing/__init__.py", line 446, in plot
    result = Plot(target, bbox, background=kwds.get("background", "white"))
  File "/home/chovanec/anaconda3/lib/python3.5/site-packages/igraph/drawing/__init__.py", line 117, in __init__
    self._surface_was_created = not isinstance(target, cairo.Surface)
AttributeError: module 'cairo' has no attribute 'Surface'

我找不到导致它的原因。