[Python] Inconsistent Behavior of Addition between int and float

I make a class that takes a number during instantiation. It only has one instance attribute, that is self.value. This class also has some methods such as __add__ and __radd__ that are proxies of the original methods. If self.value holds a float object, all these methods work well, but they raise error if self.value holds an integer object and operate with a float value. Here is my code.

class MyNumber:
def __init__(self, value):
self.value = value
def __repr__(self):
return f'{self.__class__.__name__}(value={self.value})'
def __int__(self):
return self.value.__int__()
def __float__(self):
return self.value.__float__()
def __bool__(self):
return self.value.__bool__()
def __add__(self, other):
return self.value.__add__(other)
def __radd__(self, other):
return self.value.__radd__(other)


Here I test my code.

mynumber_int = MyNumber(1)
print(mynumber_int)
print(mynumber_int + 2) # works as expected
print(3 + mynumber_int) # works as expected
#print(mynumber_int + 2.) # TypeError: unsupported operand type(s) for +: 'MyNumber' and 'float'
#print(3. + mynumber_int) # TypeError: unsupported operand type(s) for +: 'float' and 'MyNumber'

mynumber_float = MyNumber(1.)
print(mynumber_float)
print(mynumber_float + 2) # works as expected
print(3 + mynumber_float) # works as expected
print(mynumber_float + 2.) # works as expected
print(3. + mynumber_float) # works as expected


I think mynumber_int + 2. works like 3 + mynumber_float, unfortunately the first one raises error and the second one succeeds. For any explanation and help, I very appericate.

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