Change Ruby Symbol Keyed Hash Syntax on Save to the new Ruby 1.9.3 - 2.0 Syntax (Only changes symbol keys)

gistfile1.py

import sublime, sublime_plugin, os

class RubyPostProcess(sublime_plugin.EventListener):
  def on_pre_save(self, view):
    syntax = os.path.basename(view.settings().get('syntax'))
    syntax = os.path.splitext(syntax)[0]

    if syntax == "Ruby":
      replacements = []
      edit = view.begin_edit()
      regions_result = view.find_all(r":([a-z_]+)[ ]*=>[ ]* ", sublime.IGNORECASE, "\\1: ", replacements)
      for i, thisregion in reversed(list(enumerate(regions_result))):
        view.replace(edit, thisregion, replacements[i])
      view.end_edit(edit)