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Since the classes are all subclasses of _MyBase, they can be accessed via _MyBase.__subclasses__() after they have been imported:

for (module_loader, name, ispkg) in pkgutil.iter_modules([pkg_dir]):
    importlib.import_module('.' + name, __package__)
    
all_my_base_classes = {cls.__name__: cls for cls in base._MyBase.__subclasses__()}

For importing the modules, I followed the advice of Nihathrael.

Since the classes are all subclasses of _MyBase, they can be accessed via _MyBase.__subclasses__() after they have been imported:

for (module_loader, name, ispkg) in pkgutil.iter_modules([pkg_dir]):
    importlib.import_module('.' + name, __package__)
    
all_my_base_classes = {cls.__name__: cls for cls in base._MyBase.__subclasses__()}

For importing the modules, I followed the advice of Nihathrael.

Since the classes are all subclasses of _MyBase, they can be accessed via _MyBase.__subclasses__() after they have been imported:

for (module_loader, name, ispkg) in pkgutil.iter_modules([pkg_dir]):
    importlib.import_module('.' + name, __package__)
    
all_my_base_classes = {cls.__name__: cls for cls in base._MyBase.__subclasses__()}

Since the classes are all subclasses of _MyBase, they can be accessed via _MyBase.__subclasses__() after they have been imported:

for (module_loader, name, ispkg) in pkgutil.iter_modules([pkg_dir]):
    importlib.import_module('.' + name, __package__)
    
all_my_base_classes = {cls.__name__: cls for cls in base._MyBase.__subclasses__()}

For importing the modules, I followed the advice of Nihathrael.

Since the classes are all subclasses of _MyBase, they can be accessed via _MyBase.__subclasses__() after they have been imported:

for (module_loader, name, ispkg) in pkgutil.iter_modules([pkg_dir]):
    importlib.import_module('.' + name, pkg_dir)
    
all_my_base_classes = {cls.__name__: cls for cls in base._MyBase.__subclasses__()}

Since the classes are all subclasses of _MyBase, they can be accessed via _MyBase.__subclasses__() after they have been imported:

for (module_loader, name, ispkg) in pkgutil.iter_modules([pkg_dir]):
    importlib.import_module('.' + name, __package__)
    
all_my_base_classes = {cls.__name__: cls for cls in base._MyBase.__subclasses__()}