diff --git a/tests/get_sample_data.ipynb b/tests/get_sample_data.ipynb
index d46fe5ecd05249c90aba347525ef718b1fdc71a5..fd3026b97d8e66c810691733e71b357e920a8cbf 100644
--- a/tests/get_sample_data.ipynb
+++ b/tests/get_sample_data.ipynb
@@ -57,6 +57,7 @@
    "metadata": {},
    "outputs": [],
    "source": [
+    "#this cell can run 30minutes or longer.\n",
     "import time\n",
     "\n",
     "waiting_for_data = True\n",