Replace inline if statements with or

example: (x = something if (x is None) else x ) --> (x = x or something)

rest_framework/decorators.py

@@ -18,7 +18,7 @@ def api_view(http_method_names=None):
     Decorator that converts a function-based view into an APIView subclass.
     Takes a list of allowed methods for the view as an argument.
     """
-    http_method_names = ['GET'] if (http_method_names is None) else http_method_names
+    http_method_names = http_method_names or ['GET']
 
     def decorator(func):
 
@@ -142,8 +142,7 @@ def action(methods=None, detail=None, url_path=None, url_name=None, **kwargs):
                    how the `@renderer_classes` etc. decorators work for function-
                    based API views.
     """
-    methods = ['get'] if methods is None else methods
+    methods = [method.lower() for method in methods or ['get']]
-    methods = [method.lower() for method in methods]
 
     assert detail is not None, (
         "@action() missing required argument: 'detail'"

rest_framework/fields.py

@@ -345,7 +345,7 @@ class Field:
         self.initial = self.initial if (initial is empty) else initial
         self.label = label
         self.help_text = help_text
-        self.style = {} if style is None else style
+        self.style = style or {}
         self.allow_null = allow_null
 
         if self.default_empty_html is not empty:

rest_framework/utils/mediatypes.py

@@ -45,7 +45,7 @@ def order_by_precedence(media_type_lst):
 
 class _MediaType:
     def __init__(self, media_type_str):
-        self.orig = '' if (media_type_str is None) else media_type_str
+        self.orig = media_type_str or ''
         self.full_type, self.params = parse_header(self.orig.encode(HTTP_HEADER_ENCODING))
         self.main_type, sep, self.sub_type = self.full_type.partition('/')
 

rest_framework/versioning.py

@@ -81,7 +81,7 @@ class URLPathVersioning(BaseVersioning):
 
     def reverse(self, viewname, args=None, kwargs=None, request=None, format=None, **extra):
         if request.version is not None:
-            kwargs = {} if (kwargs is None) else kwargs
+            kwargs = kwargs or {}
             kwargs[self.version_param] = request.version
 
         return super().reverse(