Bug Report

Describe the bug
Pyright reports an attribute access error for the method that was added to Python's enum module in version 3.13.

Error Message

Cannot access attribute "_add_value_alias_" for class "EOTFType*"Attribute "_add_value_alias_" is unknown (reportAttributeAccessIssue)

Code Sample

fromenumimportEnumfromtypingimportAnyclassEOTFType(str,Enum):RESERVED= ("RESERVED",0)SDR= ("SDR",1)PQ= ("PQ",2)HLG= ("HLG",3)def__new__(cls,value:str,*args:Any):self=str.__new__(cls,value)self._value_=valueforainargs:self._add_value_alias_(a)# Pyright error herereturnself

Expected behavior
Pyright should recognize_add_value_alias_ as a valid method on enum classes in Python 3.13.

Environment

• Pyright version: 1.1.403
• Python version: 3.13
• Platform: macOS

Additional context
According to thePython 3.13 enum documentation,_add_value_alias_ was added in version 3.13 as a method ofEnumType to "add a new value as an alias to an existing member".

The method works correctly at runtime but Pyright's type stubs appear to be missing this new method. This affects code that uses this legitimate Python 3.13 enum feature.

Workaround
Currently using# type: ignore comment to suppress the error, but proper type stub support would be preferred.