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# File lib/rmail/message.rb, line 82
    def decode
      raise TypeError, "Can not decode a multipart message." if multipart?
      case header.fetch('content-transfer-encoding', '7bit').strip.downcase
      when 'quoted-printable'
        Utils.quoted_printable_decode(@body)
      when 'base64'
        Utils.base64_decode(@body)
      else
        @body
      end
    end