Interfaces lead to circular imports when splitting type definitions across files

I’m not sure if this issue has been raised before. Did a quick search through issues and didn’t find anything. But I was wondering if anyone had run into this issue before and there’s an existing Python solution I’m not thinking about or if this is an existing issue.

Basically, when defining a type that implements an interface, we specify the interface class that is being implemented by this new type in the Meta interface option.

class Character(graphene.Interface): 
    id = graphene.ID(required=True)
    name = graphene.String(required=True)
    friends = graphene.List(lambda: Character)

class Human(graphene.ObjectType):
    class Meta:
        interfaces = (Character, ) # <----- here

    starships = graphene.List(Starship)
    home_planet = graphene.String()

But if we would like to split the class definitions across two files:

#schema.py 

import graphene
from human import Human
from droid import Droid


class Character(graphene.Interface):
    id = graphene.ID(required=True)
    name = graphene.String(required=True)
    friends = graphene.List(lambda: Character)

   def resolve_type(cls, instance, info):
        if instance.type == 'DROID':
            return Droid
        return Human # <----- here we need to import Human




....


schema = graphene.Schema(query=Query, mutation=Mutation, types=[Human])

and

#human.py
class Human(graphene.ObjectType):
    class Meta:
        interfaces = (Character, ) # <--- would require us to import Character

    starships = graphene.List(Starship)
    home_planet = graphene.String()

then how would the Human class be able to import the Character class it needs to specify in the interfaces it implements without introducing circular imports?

[ekampf]

# interfaces.py

import graphene

class Character(graphene.Interface):
    id = graphene.ID(required=True)
    name = graphene.String(required=True)
    friends = graphene.List(lambda: Character)

   def resolve_type(cls, instance, info):
        from droid import Droid
        from human import Human
        if instance.type == 'DROID':
            return Droid
        return Human

[klairetan]

apparently, resolve_type can actually return Strings, so you can return ‘Droid’ and ‘Human’ instead of the classes themselves