diff --git a/HW4/requirements.txt b/HW4/requirements.txt
index c3795a1..73d22d5 100644
--- a/HW4/requirements.txt
+++ b/HW4/requirements.txt
@@ -26,7 +26,7 @@ olefile==0.44
 pandocfilters==1.4.1
 pexpect==4.2.1
 pickleshare==0.7.4
-Pillow==4.2.1
+Pillow==9.0.1
 prompt-toolkit==1.0.14
 ptyprocess==0.5.2
 Pygments==2.2.0