fix typing

Author: mertalev

Diff for: machine-learning/app/models/facial_recognition/recognition.py

@@ -26,7 +26,7 @@ def __init__(self, model_name: str, min_score: float = 0.7, **model_kwargs: Any)
 
     def _load(self) -> ModelSession:
         session = self._make_session(self.model_path)
-        if self.batch and session.get_inputs()[0].shape[0] != "batch":
+        if self.batch and isinstance((first_axis := session.get_inputs()[0].shape[0]), str) and first_axis != "batch":
             self._add_batch_axis(self.model_path)
             session = self._make_session(self.model_path)
         self.model = ArcFaceONNX(