Improve docs for Formula#python (python_helper)

Library/Homebrew/formula.rb

@@ -307,6 +307,10 @@ class Formula
     ]
   end
 
+  # Install python bindings inside of a block given to this method and/or
+  # call python so: `system python, "setup.py", "install", "--prefix=#{prefix}"
+  # Note that there are no quotation marks around python!
+  # <https://github.com/mxcl/homebrew/wiki/Homebrew-and-Python>
   def python(options={:allowed_major_versions => [2, 3]}, &block)
     require 'python_helper'
     python_helper(options, &block)