typing for "any class which is decorated with @dataclass_json"

[davetapley]

I think it's not possible because python/typing#246
but it would be great if I could do e.g.:

@dataclass_json
@dataclass
class Foo:
  pass

class Bar:
  pass

Then have:

T = TypeVar('T') # something else here?
def saveThis(thing: T):
  thing.to_json()

and have saveThis(Foo()) ✅ and saveThis(Bar()) ❌

Any ideas?

[cybertiger]

T = TypeVar('T', bound=DataClassJsonMixin)

Should fix it for you.