def possible_types(type)
      if type.kind.interface?
        schema.possible_types(type)
      elsif type.kind.union?
        type.possible_types
      end
    end
def possible_types(type)
      if type.kind.interface?
        schema.possible_types(type)
      elsif type.kind.union?
        type.possible_types
      end
    end
Get the possible types of a union or interface.

 type - A GraphQL::UnionType or GraphQL::InterfaceType instance.

 Returns an Array of GraphQL::ObjectType instances.