diff --git a/milatools/utils/parallel_progress.py b/milatools/utils/parallel_progress.py
index 8edcfa2a..3304024d 100644
--- a/milatools/utils/parallel_progress.py
+++ b/milatools/utils/parallel_progress.py
@@ -85,7 +85,7 @@ async def run_async_tasks_with_progress_bar(
 
     >>> import pytest, sys
     >>> if sys.platform.startswith('win'):
-    ...     pytest.skip('This doctest doesn't work properly on Windows.')
+    ...     pytest.skip("This doctest doesn't work properly on Windows.")
     >>> async def example_task_fn(report_progress: ReportProgressFn, len_of_task: int):
     ...     import random
     ...     report_progress(progress=0, total=len_of_task, info="Starting.")