diff --git a/joj3_config_generator/processers/task.py b/joj3_config_generator/processers/task.py
index 78d73b1..2cdc780 100644
--- a/joj3_config_generator/processers/task.py
+++ b/joj3_config_generator/processers/task.py
@@ -67,7 +67,7 @@ def get_executor_with(
     task_stage: task.Stage, cached: Dict[str, None]
 ) -> result.ExecutorWith:
     file_import = task_stage.files.import_
-    copy_in_files = [file for file in file_import if file not in cached]
+    copy_in_files = (file for file in file_import if file not in cached)
     file_export = task_stage.files.export
     copy_out_files = ["stdout", "stderr"]
     executor_with_config = result.ExecutorWith(
@@ -102,6 +102,8 @@ def get_executor_with(
 def fix_keyword(
     keyword_config: task.ParserKeyword, keyword_parser: result.Parser
 ) -> None:
+    if len(keyword_config.keyword) != len(keyword_config.weight):
+        raise ValueError("Keywords and weights must have the same length")
     score_groups: Dict[int, List[str]] = {}
     for keyword, score in zip(keyword_config.keyword, keyword_config.weight):
         score_groups.setdefault(score, []).append(keyword)