update to ignore attr defined

Author: jtsodapop

labelbox/schema/project.py

@@ -276,8 +276,7 @@ def _validate_datetime(string_date: str) -> None:
             """helper function validate that datetime is as follows: YYYY-MM-DD for the export"""
             if string_date:
                 try:
-                    datetime.fromisoformat(  # type: ignore[attr-defined]
-                        string_date)  # type: ignore[attr-defined]
+                    datetime.strptime(string_date, "%Y-%m-%d")
                 except:
                     raise ValueError(f"""Incorrect format for: {string_date}. 
                     Format must be \"YYYY-MM-DD\"""")