run black over stubs, add checking to travis

django-stubs-generated/db/migrations/operations/special.pyi

@@ -6,31 +6,18 @@ from django.db.migrations.state import ProjectState, StateApps
 
 from .base import Operation
 
-
 class SeparateDatabaseAndState(Operation):
     serialization_expand_args: Any = ...
     database_operations: Any = ...
     state_operations: Any = ...
-    def __init__(
-        self,
-        database_operations: List[Any] = ...,
-        state_operations: List[CreateModel] = ...,
-    ) -> None: ...
+    def __init__(self, database_operations: List[Any] = ..., state_operations: List[CreateModel] = ...) -> None: ...
     def deconstruct(self): ...
     def state_forwards(self, app_label: str, state: ProjectState) -> None: ...
     def database_forwards(
-        self,
-        app_label: str,
-        schema_editor: DatabaseSchemaEditor,
-        from_state: ProjectState,
-        to_state: ProjectState,
+        self, app_label: str, schema_editor: DatabaseSchemaEditor, from_state: ProjectState, to_state: ProjectState
     ) -> None: ...
     def database_backwards(
-        self,
-        app_label: str,
-        schema_editor: DatabaseSchemaEditor,
-        from_state: ProjectState,
-        to_state: ProjectState,
+        self, app_label: str, schema_editor: DatabaseSchemaEditor, from_state: ProjectState, to_state: ProjectState
     ) -> None: ...
     def describe(self): ...
 
@@ -53,12 +40,8 @@ class RunSQL(Operation):
     @property
     def reversible(self): ...
     def state_forwards(self, app_label: Any, state: Any) -> None: ...
-    def database_forwards(
-        self, app_label: Any, schema_editor: Any, from_state: Any, to_state: Any
-    ) -> None: ...
-    def database_backwards(
-        self, app_label: Any, schema_editor: Any, from_state: Any, to_state: Any
-    ) -> None: ...
+    def database_forwards(self, app_label: Any, schema_editor: Any, from_state: Any, to_state: Any) -> None: ...
+    def database_backwards(self, app_label: Any, schema_editor: Any, from_state: Any, to_state: Any) -> None: ...
     def describe(self): ...
 
 class RunPython(Operation):
@@ -81,18 +64,10 @@ class RunPython(Operation):
     def reversible(self) -> bool: ...
     def state_forwards(self, app_label: str, state: ProjectState) -> None: ...
     def database_forwards(
-        self,
-        app_label: str,
-        schema_editor: DatabaseSchemaEditor,
-        from_state: ProjectState,
-        to_state: ProjectState,
+        self, app_label: str, schema_editor: DatabaseSchemaEditor, from_state: ProjectState, to_state: ProjectState
     ) -> None: ...
     def database_backwards(
-        self,
-        app_label: str,
-        schema_editor: DatabaseSchemaEditor,
-        from_state: ProjectState,
-        to_state: ProjectState,
+        self, app_label: str, schema_editor: DatabaseSchemaEditor, from_state: ProjectState, to_state: ProjectState
     ) -> None: ...
     def describe(self): ...
     @staticmethod