diff --git a/216_mito_unet__xferlearn_12_training_images.py b/216_mito_unet__xferlearn_12_training_images.py
index 9905bb61e..4a2edda55 100644
--- a/216_mito_unet__xferlearn_12_training_images.py
+++ b/216_mito_unet__xferlearn_12_training_images.py
@@ -26,7 +26,7 @@
 
 Option 2 (especially for Google Colab):
 Work with Tensorflow 1.x
-In google colab, add this as your fitst line.
+In google colab, add this as your first line.
 %tensorflow_version 1.x
 """