Remove six.with_metaclass calls

graphene/types/enum.py

@@ -1,7 +1,4 @@
 from collections import OrderedDict
-
-import six
-
 from graphene.utils.subclass_with_meta import SubclassWithMeta_Meta
 
 from ..pyutils.compat import Enum as PyEnum
@@ -66,7 +63,7 @@ def from_enum(cls, enum, description=None, deprecation_reason=None):  # noqa: N8
         return type(meta_class.enum.__name__, (Enum,), {"Meta": meta_class})
 
 
-class Enum(six.with_metaclass(EnumMeta, UnmountedType, BaseType)):
+class Enum(UnmountedType, BaseType, metaclass=EnumMeta):
     @classmethod
     def __init_subclass_with_meta__(cls, enum=None, _meta=None, **options):
         if not _meta:

graphene/utils/subclass_with_meta.py

@@ -1,7 +1,5 @@
 from inspect import isclass
 
-import six
-
 from ..pyutils.init_subclass import InitSubclassMeta
 from .props import props
 
@@ -18,7 +16,7 @@ def __repr__(cls):
         return "<{} meta={}>".format(cls.__name__, repr(cls._meta))
 
 
-class SubclassWithMeta(six.with_metaclass(SubclassWithMeta_Meta)):
+class SubclassWithMeta(metaclass=SubclassWithMeta_Meta):
     """This class improves __init_subclass__ to receive automatically the options from meta"""
 
     # We will only have the metaclass in Python 2