[Python] How do I type a generic subclass correctly?

Here is some example code:

I have my underlying generic object.

T = TypeVar("T", str, int, bytes)


class MyObj(Generic[T]):
id: T


and some implementations

class MyObjImplInt(MyObj[int]): ...
class MyObjImplStr(MyObj[str]): ...


obj_int = MyObjImplInt()
type(obj_int.id) # int

obj_str = MyObjImplStr()
type(obj_str.id) # str


Now I have built a manager for these objects

TObj = TypeVar("TObj", bound=MyObj)

class MyObjMgr(Generic[TObj, T]):
objs: list[TObj]

def __init__(self, objs: list[TObj]):
self.objs = objs

def get_by_id(self, obj_id: T):
return [e for e in self.objs if e.id == obj_id]


class MyObjMgrInts(MyObjMgr[MyObjImplInt, int]): ...
class MyObjMgrStrs(MyObjMgr[MyObjImplStr, str]): ...


My issue is that I have to provide the type T for MyObjMgr(Generic[TObj, T]) in order to specify the id type of the underlying object. Is there a way to infer T from TObj[T]?

i.e. just write this:

class MyObjMgr2(Generic[TObj]):
objs: list[TObj]

def __init__(self, objs: list[TObj]):
self.objs = objs

def get_by_id(self, obj_id: T@TObj): # err here
return [e for e in self.objs if e.id == obj_id]


class MyObjMgr2Ints(MyObjMgr2[MyObjImplInt]): ...

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