update type hinting

selfdrive/car/car_helpers.py

@@ -1,4 +1,5 @@
 import os
+from typing import Any, Dict, List
 
 from common.params import Params
 from common.basedir import BASEDIR
@@ -58,7 +59,8 @@ def load_interfaces(brand_names):
   return ret
 
 
-def get_interface_attr(attr):
+def get_interface_attr(attr: str) -> Dict[str, Any]:
+  # returns given attribute from each interface
   brand_names = {}
   for car_folder in [x[0] for x in os.walk(BASEDIR + '/selfdrive/car')]:
     try:
@@ -70,11 +72,8 @@ def get_interface_attr(attr):
   return brand_names
 
 
-def _get_interface_names():
-  # read all the folders in selfdrive/car and return a dict where:
-  # - keys are all the car names that which we have an interface for
-  # - values are lists of specific car models for a given brand
-
+def _get_interface_names() -> Dict[str, List[str]]:
+  # returns a dict of brand name and its respective models
   brand_names = {}
   for brand_name, model_names in get_interface_attr("CAR").items():
     model_names = [getattr(model_names, c) for c in model_names.__dict__.keys() if not c.startswith("__")]