Convert to mIRC format
        :param preserve_original: if the current ColorString instance was created from mIRC text,
               then just return the original string
        :return:

def to_irc(self, preserve_original=True):
        """
        Convert to mIRC format
        :param preserve_original: if the current ColorString instance was created from mIRC text,
               then just return the original string
        :return:
        """
        if preserve_original and self.original_type == 'irc':
            return self.original_bytes
        res = []
        for i in self.parts:
            res.append(i.to_irc())
        s = ''.join(res) + '\x03\x0f'
        return s.encode('utf8')