class RuboCop::MagicComment::SimpleComment

def extract_frozen_string_literal

Other tags:
    See: https://github.com/ruby/ruby/blob/78b95b4/parse.y#L7134-L7138 - 
def extract_frozen_string_literal
  extract(/\A\s*#\s*#{KEYWORDS[:frozen_string_literal]}:\s*(#{TOKEN})\s*\z/io)
end