如何获取从 Python 3 中的模块导入的所有类的列表？

Question

I want to create a list consisting of the names of all classes I import from a certain folder.

At the moment I have something like this:

from .my_classes import Class1, Class2, Class3
list_of_classes = [Class1.__name__, Class2.__name__, Class3.__name__]

But I want to convert it to something less manual:

from .my_classes import *

# .my_classes is obviously not working
list_of_classes = [cls.__name__ for cls in .my_classes]

How can I get .my_classes as a list?

.my_classes is a folder with this structure:

my_classes
|
|--__init__.py
|--some_classes_here.py
|--some_more_classes_here.py

Answer 1

Basically the imported objects become attributes of your module. So calling vars() will put all the parameters.

If you put it after your import you should see it.

Please note that if you import import x as y you will see y and not x

example:

import collections
import re
print([x for x in vars() if  not (x.startswith('__') and x.endswith('__'))])
['collections', 're']

Answer 2

You can use locals() to collect the names in your current namespace and then inspect which module they came from using the __module__ attribute. This only works for classes and functions.

from .my_classes import *

classes = []
for name, item in locals().copy().items():
    try:
        if item.__module__ == 'my_classes':
            classes.append(item.__name__)
    except AttributeError:
        continue

classes
# returns:
['Class1', 'Class2', 'Class3']