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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:
 async def unban(self, channel, target, range=0):
 """ Unban user from channel. Target can be either a user or a host. See ban documentation for the range parameter. """

        if target in self.users:
            host = self.users[target]['hostname']
        else:
            host = target

        host = self._format_host_range(host, range)
        mask = self._format_host_mask('*', '*', host)
        await self.rawmsg('MODE', channel, '-b', mask)