diff --git a/Library/Homebrew/formula.rb b/Library/Homebrew/formula.rb
index bf64044b33..4a24552eff 100644
--- a/Library/Homebrew/formula.rb
+++ b/Library/Homebrew/formula.rb
@@ -307,7 +307,7 @@ class Formula
 
   def python(options={:allowed_major_versions => [2, 3]}, &block)
     require 'python_helper'
-    self.instance_eval{ python_helper(options, &block) }
+    python_helper(options, &block)
   end
 
   # Explicitly only execute the block for 2.x (if a python 2.x is available)