OSError: no library called "libcairo-2" was found
cannot load library 'E:\Seafile\Python\lib\Graphviz\bin\cairo.dll': error 0xc1
cannot load library 'libcairo.so.2': error 0x7e
cannot load library 'libcairo.2.dylib': error 0x7e
cannot load library 'libcairo-2.dll': error 0x7e
去https://pypi.org/project/pycairo/#files下载对应的文件
64位 windows + python 3.8 就下载 pycairo-1.20.0-cp38-cp38-win_amd64.whl
DOS下 安装
pip install pycairo-1.20.0-cp38-cp38-win_amd64.whl