[Python] Reconciling dataclasses with property: None as default value [duplicate]

Following Dataclasses and property decorator, via this comment I ended up in this tutorial on how to define @property in a dataclass.

I have modified the solution, it's attempt 5 (the last attempt), to use a None default value for the property.

I ended up with:

from dataclasses import dataclass, field

@dataclass
class Vehicle:
wheels: int|None = None
_wheels: int|None = field(init=False, repr=False, default=None)

@property
def wheels(self) -> int|None:
print("getting wheels")
return self._wheels

@wheels.setter
def wheels(self, wheels: int|None):
print("setting wheels to", wheels)
self._wheels = wheels


Now when declaring an empty object

Vehicle()


I get

setting wheels to <property object at 0x0000019DB0ADF100>
getting wheels
Vehicle(wheels=<property object at 0x0000019DB0ADF100>)


Why do I get the property object instead of None?

How can I properly define a None default value here?

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