我的 Travis 构建目前在 pylint 失败并出现错误：
Traceback (most recent call last):
File "/home/travis/virtualenv/python3.3.6/bin/pylint", line 11, in <module>
sys.exit(run_pylint())
File "/home/travis/virtualenv/python3.3.6/lib/python3.3/site-packages/pylint/__init__.py", line 17, in run_pylint
from pylint.lint import Run
File "/home/travis/virtualenv/python3.3.6/lib/python3.3/site-packages/pylint/lint.py", line 75, in <module>
import astroid
File "/home/travis/virtualenv/python3.3.6/lib/python3.3/site-packages/astroid/__init__.py", line 62, in <module>
from astroid.nodes import *
File "/home/travis/virtualenv/python3.3.6/lib/python3.3/site-packages/astroid/nodes.py", line 23, in <module>
from astroid.node_classes import (
File "/home/travis/virtualenv/python3.3.6/lib/python3.3/site-packages/astroid/node_classes.py", line 34, in <module>
from functools import singledispatch as _singledispatch
ImportError: cannot import name singledispatch
我目前用于 pylint 的构建命令是：
find -name "*.py" -not -path "*/migrations/*" -not -name "apps.py" -not -name "wsgi.py" -not -name "manage.py" | xargs pylint --load-plugins pylint_django
它适用于我的本地 Windows 机器（在 bash shell 中）。我的构建脚本的其余部分是：
language: python
python:
- "3.3"
- "3.4"
- "3.5"
- "3.5-dev"
- "3.6"
- "3.6-dev"
- "3.7-dev"
install:
- pip install flake8
- pip install flake8-docstrings
- pip install pylint
- pip install pylint-django
- pip install -r requirements.txt
- npm install -g stylelint
- npm install stylelint-config-standard --save-dev
- npm install -g eslint
- npm install -g eslint-config-standard eslint-plugin-standard eslint-plugin-promise eslint-plugin-import eslint-plugin-node
script:
- flake8 . --exclude migrations,tests.py,__init__.py,apps.py,manage.py
- find -name "*.py" -not -path "*/migrations/*" -not -name "apps.py" -not -name "wsgi.py" -not -name "manage.py" | xargs pylint --load-plugins pylint_django
- stylelint **/static/**/*.css
- eslint . --ignore-pattern '/staticfiles/*'
我应该如何解决这个错误？提前致谢。