Проверил метки на символы не из словаря.

scripts/dataset_validation.py

@@ -22,14 +22,23 @@ def check_images(directory_path: str):
         except Exception:
             print(file)
 
-def check_labels(dir_path: str) -> int:
+def check_labels(dir_path: str):
     for filename in os.listdir(dir_path):
         name, extension = filename.split(".")
         if len(name) != 17:
             print(filename)
 
+def check_symbols(dir_path: str):
+    with open(os.path.join(dir_path, "dict.txt"), "r") as dict_file:
+        dict_content = dict_file.readlines()
+        dict_chars = set(char.strip() for char in dict_content)
+        for filename in os.listdir(os.path.join(dir_path, "images")):
+            label, extension = filename.split(".")
+            if any([char not in dict_chars for char in label]):
+                print(filename)
 
 # rename_files("train_data/images/")
 # check_images("train_data/images/")
-check_labels("train_data/images/")
+# check_labels("train_data/images/")
+check_symbols("train_data/")