def rfc_persona_moral
      consonants_n_amp = CONSONANTS + ['Ñ', '&']
      all_letters = consonants_n_amp + VOWELS
      date = ::Time.at(rand * ::Time.now.to_f).strftime('%y%m%d')
      "#{fetch_sample(all_letters, count: 3).join}#{date}#{fetch_sample(HOMOCLAVE, count: 3).join}"
    end
def rfc_persona_moral
      consonants_n_amp = CONSONANTS + ['Ñ', '&']
      all_letters = consonants_n_amp + VOWELS
      date = ::Time.at(rand * ::Time.now.to_f).strftime('%y%m%d')
      "#{fetch_sample(all_letters, count: 3).join}#{date}#{fetch_sample(HOMOCLAVE, count: 3).join}"
    end
http://es.wikipedia.org/wiki/Registro_Federal_de_Contribuyentes_(M%C3%A9xico)
 Registro Federal de Contribuyentes (R.F.C.) para persona moral