chore: remove unused import and black formatting

graphql/type/schema.py

@@ -4,25 +4,21 @@
  from collections import Iterable
 
 from collections import namedtuple
-from typing import Dict, Union, List, Optional, cast, NamedTuple
+from typing import Dict, Union, List, Optional
 
 from .definition import (
- GraphQLAbstractType,
  GraphQLNamedType,
  GraphQLInterfaceType,
  GraphQLObjectType,
  GraphQLUnionType,
  GraphQLType,
- is_union_type,
- is_interface_type,
- is_object_type,
 )
 from .directives import GraphQLDirective, specified_directives
 from .introspection import IntrospectionSchema
 from .typemap import GraphQLTypeMap
 
 
-InterfaceImplementations = namedtuple('InterfaceImplementations', 'objects, interfaces')
+InterfaceImplementations = namedtuple("InterfaceImplementations", "objects, interfaces")
 
 
 class GraphQLSchema(object):

graphql/type/typemap.py

@@ -164,9 +164,7 @@ def assert_object_implements_interface(
  )
 
  assert is_type_sub_type_of(
- cast("GraphQLSchema", schema),
- object_field.type,
- interface_field.type
+ cast("GraphQLSchema", schema), object_field.type, interface_field.type
  ), '{}.{} expects type "{}" but {}.{} provides type "{}".'.format(
  interface,
  field_name,

graphql/validation/rules/overlapping_fields_can_be_merged.py

@@ -33,7 +33,7 @@
  InlineFragment,
  SelectionSet,
  )
- from ...type.definition import GraphQLField, GraphQLScalarType
+ from ...type.definition import GraphQLField
  from typing import List, Union, Any, Optional, Dict, Tuple