[Python] Dynamic call to attribute's method ends up to calling it on wrong instance (after...

I'm encountering a behavior that surprises me on dynamic calls:

I have a class that acts as an attribute for another class. When the container class resets this attribute, the methods of the attribute class are applied to the old instance if called dynamically, and to the new instance if called directly.

What must be done to ensure that dynamic calls are made to an attribute that has been reset?

class attributeClass():
def __init__(self):
self.dummy = 0

def printDummy(self):
print('id : '+hex(id(self)))
print(self.dummy)

def modifyDummy(self, newValue):
self.dummy = newValue



class ContainerClass():
def __init__(self):
self.attributeObject = attributeClass()
self.dic = {'dynamicCall': self.attributeObject.printDummy }

def resetAttribute(self):
self.attributeObject = attributeClass()



def main():
containerObject = ContainerClass() # create instance of ContainerClass
print('--A--: create instance of ContainerClass')
containerObject.attributeObject.printDummy() # call printDummy directly
containerObject.dic['dynamicCall']() # call printDummy dynamically

print('--B--: call to modifyDummy(5)')
containerObject.attributeObject.modifyDummy(5) # change the dummy value
containerObject.attributeObject.printDummy() # direct call
containerObject.dic['dynamicCall']() # dynamic call

print('--C--: call the reset function')
containerObject.resetAttribute() # reset the container's attribute "attributeClass"
containerObject.attributeObject.printDummy() # direct
containerObject.dic['dynamicCall']() # dynamic



if __name__ == '__main__':
main()


the above code has as output (addresses may vary):

--A--: create instance of ContainerClass

id : 0x22ea3ad6ba0

0

id : 0x22ea3ad6ba0

0

--B--: call to modifyDummy(5)

id : 0x22ea3ad6ba0

5

id : 0x22ea3ad6ba0

5

--C--: call the reset function

id : 0x22ea3d78b90

0

id : 0x22ea3ad6ba0

5

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