diff --git a/colab_env/tagging.py b/colab_env/tagging.py
index 169f38c..cf1aae9 100644
--- a/colab_env/tagging.py
+++ b/colab_env/tagging.py
@@ -221,6 +221,7 @@ def predict(
                 )
                 sorted_character_strings_str: List[str] = [x[0] for x in sorted_character_strings]
                 sorted_character_strings_str = [x.replace(' ', '_') for x in sorted_character_strings_str]
+                ret_string += ","
                 ret_string += ",".join(sorted_character_strings_str)
 
             ret_strings.append(ret_string)