另一个原因导致了这个问题

file.py

#!/bin/python
from bs4 import BeautifulSoup

如果你的默认python是pyyhon2

$ file $(which python)
/sbin/python: symbolic link to python2

File.py在这种情况下需要python3 (bs4) 你不能像这样用python2执行这个模块:

$ python file.py
# or
$ file.py
# or
$ file.py # if locate in $PATH

两种方法来修复这个错误，

# should be to make python3 as default by symlink
$ rm $(which python) && ln -s $(which python3) /usr/bin/python
# or use alias
alias python='/usr/bin.../python3'

或者将file.py中的shebang修改为

#!/usr/bin/...python3

通过编写print (sys.path)修复了我的问题，并发现尽管清洁安装，python仍在使用过时的包。删除这些会使python自动使用正确的包。

如果你时间紧迫，其他方法都失败了:

import sys
import os
wd = '/path/to/current/script/'
sys.path.append(wd)
os.chdir(wd)
print(os.getcwd())
print(sys.path)

当我在LPTHW中做这个练习时，我遇到了非常相似的情况;我永远无法让Python识别我调用的目录中有文件。但最后我还是让它工作了。我所做的，以及我所推荐的，是这样做的:

(注意:从你最初的文章中，我假设你使用的是基于* nix的机器，并从命令行运行，所以这个建议是为你量身定做的。因为我运行Ubuntu，这是我所做的)

Change directory (cd) to the directory above the directory where your files are. In this case, you're trying to run the mountain.py file, and trying to call the toolkit.interface.py module, which are in separate directories. In this case, you would go to the directory that contains paths to both those files (or in other words, the closest directory that the paths of both those files share). Which in this case is the toolkit directory. When you are in the toolkit directory, enter this line of code on your command line: export PYTHONPATH=. This sets your PYTHONPATH to ".", which basically means that your PYTHONPATH will now look for any called files within the directory you are currently in, (and more to the point, in the sub-directory branches of the directory you are in. So it doesn't just look in your current directory, but in all the directories that are in your current directory). After you've set your PYTHONPATH in the step above, run your module from your current directory (the toolkit directory). Python should now find and load the modules you specified.

一个简单的解决方案是使用python -m PIP install <library-name>来安装模块，而不是PIP install <library-name> 在管理限制的情况下，您可以使用sudo

对我来说，将该文件作为模块运行很有帮助。

而不是

python myapp/app.py

使用

python -m myapp.app

这并不完全相同，但在某些情况下这可能是一种更好的方法。