Fix Flask REST API (#7210)

utils/flask_rest_api/restapi.py

 """
-Run a rest API exposing the yolov5s object detection model
+Run a Flask REST API exposing a YOLOv5s model
 """
 import argparse
 import io
@@ -31,7 +31,10 @@ def predict():
 if __name__ == "__main__":
     parser = argparse.ArgumentParser(description="Flask API exposing YOLOv5 model")
     parser.add_argument("--port", default=5000, type=int, help="port number")
-    args = parser.parse_args()
+    opt = parser.parse_args()
+
+    # Fix known issue urllib.error.HTTPError 403: rate limit exceeded https://github.com/ultralytics/yolov5/pull/7210
+    torch.hub._validate_not_a_forked_repo = lambda a, b, c: True
 
     model = torch.hub.load("ultralytics/yolov5", "yolov5s", force_reload=True)  # force_reload to recache
-    app.run(host="0.0.0.0", port=args.port)  # debug=True causes Restarting with stat
+    app.run(host="0.0.0.0", port=opt.port)  # debug=True causes Restarting with stat