[I] Unexpected primitive based Enum (de)serialization [airflow]

[via GitHub]

mixilchenko opened a new issue, #51016:
URL: https://github.com/apache/airflow/issues/51016

   ### Apache Airflow version
   
   main (development)
   
   ### If "Other Airflow 2 version" selected, which one?
   
   _No response_
   
   ### What happened?
   
   When enumeration inherits some primitive type (e.g. str, int), 
deserialization makes the value primitive as well.
   ```python
   import enum
   from airflow.serialization.serde import deserialize, serialize
   
   class MyEnum(enum.IntEnum):
       A = 1
       B = 2
   
   value = MyEnum.A
   res = deserialize(serialize(value))
   assert res is MyEnum.A, f'{type(res)=}, {res=}'
   # AssertionError: type(res)=<class 'int'>, res=1
   ```
   
   ### What you think should happen instead?
   
   This is little unexpected for me as a user and for mypy
   ```python
   @task
   def my_task(v: MyEnum):
       assert is instance(v, MyEnum), 'fine for mypy, fails in runtime'
       v = MyEnum(v)
   ...
   my_task(MyEnum.A)
   ```
   
   The other issue is that if I add airflow compatible custom serialization the 
result is incorrect too
   ```python
   class MyEnum(enum.IntEnum):
       A = 1
       B = 2
   
       def serialize(self):
           return f'{self.name}.{self.value}'
   
   res = serialize(MyEnum.A)
   assert res == 'A.1', f'{type(res)=}, {res=}'
   # AssertionError: type(res)=<class 'int'>, res=1
   ```
   
   I would expect one of
   - implement default serialization and deserialization for enums
   - fail with `TypeError: cannot serialize object of type <enumeration 
'MyEnum'>` unless it implements the interface and is registered for 
deserialization (as it happens for enums that do not inherit primitive)
   
   ### How to reproduce
   
   See the snippet above
   
   ### Operating System
   
   Debian GNU/Linux 12 (bookworm)
   
   ### Versions of Apache Airflow Providers
   
   _No response_
   
   ### Deployment
   
   Virtualenv installation
   
   ### Deployment details
   
   _No response_
   
   ### Anything else?
   
   _No response_
   
   ### Are you willing to submit PR?
   
   - [x] Yes I am willing to submit a PR!
   
   ### Code of Conduct
   
   - [x] I agree to follow this project's [Code of 
Conduct](https://github.com/apache/airflow/blob/main/CODE_OF_CONDUCT.md)
   


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