diff --git a/Library/Homebrew/requirements/python_dependency.rb b/Library/Homebrew/requirements/python_dependency.rb
index 21d3c8af26..4f8bcf04fc 100644
--- a/Library/Homebrew/requirements/python_dependency.rb
+++ b/Library/Homebrew/requirements/python_dependency.rb
@@ -31,7 +31,7 @@ class PythonInstalled < Requirement
     end
   end
 
-  def initialize(default_version="2.6", tags=[] )
+  def initialize(default_version="2.6", tags=[])
     tags = [tags].flatten
     # Extract the min_version if given. Default to default_version else
     if /(\d+\.)*\d+/ === tags.first.to_s