循环导入以修复 pylint 中的 R0401

Question

Pylint 抱怨 NLTK 包特定文件的循环导入错误代码为 R0401，例如

nltk/nltk/ccg/lexicon.py:1: [R0401(cyclic-import), ] Cyclic import (nltk -> nltk.internals)
nltk/nltk/ccg/lexicon.py:1: [R0401(cyclic-import), ] Cyclic import (nltk.corpus -> nltk.tokenize -> nltk.tokenize.punkt -> nltk.probability)
nltk/nltk/ccg/lexicon.py:1: [R0401(cyclic-import), ] Cyclic import (nltk.corpus -> nltk.tokenize -> nltk.tokenize.texttiling)
nltk/nltk/ccg/lexicon.py:1: [R0401(cyclic-import), ] Cyclic import (nltk.draw.tree -> nltk.tree)
nltk/nltk/ccg/lexicon.py:1: [R0401(cyclic-import), ] Cyclic import (nltk.tree -> nltk.treeprettyprinter)
nltk/nltk/ccg/lexicon.py:1: [R0401(cyclic-import), ] Cyclic import (nltk.grammar -> nltk.parse.pchart)
nltk/nltk/ccg/lexicon.py:1: [R0401(cyclic-import), ] Cyclic import (nltk.stem -> nltk.stem.porter)
nltk/nltk/ccg/lexicon.py:1: [R0401(cyclic-import), ] Cyclic import (nltk.classify.maxent -> nltk.classify.tadm)

完整列表在https://github.com/nltk/nltk/issues/2113

但是看看进口：

from __future__ import unicode_literals from 

import re
from collections import defaultdict

from nltk.ccg.api import PrimitiveCategory, Direction, CCGVar, FunctionalCategory
from nltk.compat import python_2_unicode_compatible
from nltk.internals import deprecated

from nltk.sem.logic import *

但是看看 nltk.internals https://github.com/nltk/nltk/blob/develop/nltk/internals.py ，没有任何循环导入指向 nltk.ccg.lexicon:

from __future__ import print_function

import subprocess
import os
import fnmatch
import re
import warnings
import textwrap
import types
import sys
import stat
import locale

# Use the c version of ElementTree, which is faster, if possible:
try:
    from xml.etree import cElementTree as ElementTree
except ImportError:
    from xml.etree import ElementTree

from six import string_types

from nltk import __file__
from nltk import compat

R0401(cyclic-import) 消息是什么意思？

查看 nltk.ccg.lexicon.py 和 nltk.internals.py 没有任何循环导入，所以问题如何解决。

Answer 1

不确定为什么 pylint 在 nltk/nltk/ccg/lexicon.py 文件中报告这些，但是可以在错误消息的右侧看到循环导入本身。

报第一个错误：Cyclic import (nltk -> nltk.internals):根__init__.py has an import from nltk.internals, and internals.py有一个包根的导入，很明显是循环导入

循环导入以修复 pylint 中的 R0401

Cyclic Imports to fix R0401 from pylint

python

pylint

nltk

cyclic-dependency