[Python] Importing multiple modules containing identically named class in python

I would like to import optional GUI elements defined in separate .py files and add/remove these dynamically from the main GUI. The optional elements are defined in a text configuration file and thus the file names are not known in advance. My original idea was to impose a common format - the main class would be identically named in all module files. I found that the simplest implementation of this behaves in an unexpected way. Although the imported objects appear to have distinct names, there is in fact cross-talk. This demonstrates the issue and a workaround that I found on SE (commented out):

from kivy.app import App
from kivy.uix.boxlayout import BoxLayout
from kivy.uix.floatlayout import FloatLayout
from kivy.uix.button import Button
from kivy.lang import Builder
import importlib

Builder.load_string('''
<MainWidget>:
orientation: 'vertical'
BoxLayout:
Button:
text: "Load Mod 1"
on_press:
root.load_module(self.text)
Button:
text: "Load Mod 2"
on_press:
root.load_module(self.text)
Button:
text: "Unload all"
on_press:
dock.clear_widgets()
FloatLayout:
id: dock
''')

class MainWidget(BoxLayout):

def load_module(self, hint):

self.ids.dock.clear_widgets()

if "1" in hint:
self.module = importlib.import_module("Mod1").Module()#PROBLEMATIC
#module = importlib.import_module("Mod1")
#class_ = getattr(module, "Module1")
#self.module = class_()
if "2" in hint:
self.module = importlib.import_module("Mod2").Module()#PROBLEMATIC
#module = importlib.import_module("Mod2")
#class_ = getattr(module, "Module2")
#self.module = class_()

self.ids.dock.add_widget(self.module)

class MyApp(App):
def build(self):
return MainWidget()

if __name__ == '__main__':
MyApp().run()


Mod1.py:

from kivy.uix.floatlayout import FloatLayout
from kivy.lang import Builder

Builder.load_string('''
#<Module1>:
<Module>: #PROBLEMATIC
size_hint: None, None
size: self.parent.size if self.parent else self.size
pos: self.parent.pos if self.parent else self.pos
Button:
size_hint: None, None
width: self.parent.width / 3
height: self.parent.height
pos: self.parent.pos
text: "Mod 1"
on_press: print(root); print([x for x in dir(root) if 'method' in str(x)])
''')

#class Module1(FloatLayout):
class Module(FloatLayout): #PROBLEMATIC

def __init__(self, **kwargs):
super(FloatLayout, self).__init__(**kwargs)

def dummymethod1(self):
pass


Mod2.py:

from kivy.uix.floatlayout import FloatLayout
from kivy.lang import Builder

Builder.load_string('''
#<Module2>:
<Module>: #PROBLEMATIC
size_hint: None, None
size: self.parent.size if self.parent else self.size
pos: self.parent.pos if self.parent else self.pos
Button:
size_hint: None, None
width: self.parent.width / 3
height: self.parent.height
pos: (self.parent.x + self.parent.width / 2) , self.parent.y
text: "Mod 2"
on_press: print(root); print([x for x in dir(root) if 'method' in str(x)])
''')

#class Module2(FloatLayout):
class Module(FloatLayout): #PROBLEMATIC

def __init__(self, **kwargs):
super(FloatLayout, self).__init__(**kwargs)

def dummymethod2(self):
pass


It appears that although the modules have distinct names Mod1 and Mod2, the main class having the same name is a problem. Once both modules have been imported at least once, both appear in the GUI regardless which one is actually activated.

Although my workaround works to prevent this unwanted behaviour, I would like to know what causes it. Is this to do with how importing works in Python in general, or a Kivy specific issue? Is there another way to deal with this that would allow for identically-names classes in otherwise distinct modules?

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