Add tests

Signed-off-by: Tushar Goel <tushar.goel.dav@gmail.com>

Author: TG1999

tests/test_codestyle.py

@@ -27,7 +27,11 @@ def test_codestyle(self):
         try:
             subprocess.check_output(args.split())
         except Exception as e:
+            print("===========================================================")
+            print(e.output)
+            print("===========================================================")
             raise Exception(
                 "Unsorted imports, please sort your imports using isort. "
-                "Alternatively, run ``make valid``"
+                "Alternatively, run ``isort .``",
+                e.output,
             ) from e