我的文件结构：
----foo.py
----boo.py
----tests_folder
-----------------test_foo.py
-----------------__init__.py
在foo.py中，我有import boo。
我的test_foo.py包含：
import sys
sys.path.insert(0, 'd:\path\to\foo\and\bo')
import foo
似乎pytest库无法访问boo.py，而我得到ModuleNotFoundError: No module named 'boo'。任何想法可能是什么原因？
运行时：
import sys
sys.path.insert(0, 'd:\Python\Projects\gym-cards\gym_cards\envs')
print(help('modules'))
foo文件中的import boo也导致Pycharm发出警告，因为它没有看到警告。这很奇怪，因为一切正常。这里应该列出嘘吗？
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