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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _fmt(self, tag, msg):
 """Format a string for inclusion in the exception's string representation. If msg is None, format to empty string. If msg has a single line, format to: tag: msg If msg has multiple lines, format to: tag: line 1 line 2 Msg is truncated to 1024 chars. """

        msg = msg or '<unset>'
        msg = str(msg)
        msg = msg.strip()
        if not msg:
            return
        if len(msg) > 2048:
            msg = msg[:1024] + '...'
        if msg.count('\n') <= 1:
            return '{}: {}\n'.format(tag, msg.strip())
        else:
            return '{}:\n  {}\n'.format(tag, msg.replace('\n', '\n  ').strip())