class Hash
  def symbolize_keys(item=self)
    case item
    when Array
      item.map do |i|
        symbolize_keys(i)
      end
    when Hash
      Hash[
           item.map do |key, value|
             new_key = key.is_a?(String) ? key.to_sym : key
             new_value = symbolize_keys(value)
             [new_key, new_value]
           end
          ]
    else
      item
    end
  end
end