diff --git a/Library/Homebrew/utils/pypi.rb b/Library/Homebrew/utils/pypi.rb
index c24b3aa6a5..d60b09c30b 100644
--- a/Library/Homebrew/utils/pypi.rb
+++ b/Library/Homebrew/utils/pypi.rb
@@ -13,6 +13,7 @@ module PyPI
     diffoscope
     dxpy
     molecule
+    xonsh
   ].freeze
 
   @pipgrip_installed = nil