Python: get only classes defined in imported module with dir()?

Question

I've got a module written in Python. I now want to import it into another script and list all classes I defined in this module. So I try:

>>> import my_module
>>> dir(my_module)
['BooleanField', 'CharField', 'DateTimeField', 'DecimalField', 'MyClass', 'MySecondClass', 'ForeignKeyField', 'HStoreField', 'IntegerField', 'JSONField', 'TextField', '__builtins__', '__doc__', '__file__', '__name__', '__package__', 'datetime', 'db', 'division', 'os', 'struct', 'uuid']

The only two classes which I defined in my_module are MyClass and MySecondClass, the other stuff are all things that I imported into my_module.

I now want to somehow be able to get a list of all classes which are defined in my_module without getting all the other stuff. Is there a way to do this in Python?

Answer 1

Use the inspect module to inspect live objects:

>>> import inspect
>>> import my_module
>>> [m[0] for m in inspect.getmembers(my_module, inspect.isclass) if m[1].__module__ == 'my_module']

That should then work, getting every class defined within that my_module.

Answer 2

You can use Python Class Browser

import pyclbr
module_name = 'your_module'
module_info = pyclbr.readmodule(module_name)
print(module_info)

for item in module_info.values():
    print(item.name)

it will list all classes defined in your_module

Answer 3

If you really want to use dir(), here it is:

>>> import module
>>> [eval("module." + objname) for objname in dir(module) if type(eval("module." + objname)) is type]

or (script form)

import module
classes = []
for objname in dir(module):
    obj = eval("module." + objname)
    if type(obj) is type:
        classes.append(obj)
print(classes)

But this uses the "eval" function, and is really not safe for use. I'd stick to the chosen answer