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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 get_waiter(self, waiter_name):
 """Returns an object that can wait for some condition. :type waiter_name: str :param waiter_name: The name of the waiter to get. See the waiters section of the service docs for a list of available waiters. :returns: The specified waiter object. :rtype: botocore.waiter.Waiter """

        config = self._get_waiter_config()
        if not config:
            raise ValueError("Waiter does not exist: %s" % waiter_name)
        model = waiter.WaiterModel(config)
        mapping = {}
        for name in model.waiter_names:
            mapping[xform_name(name)] = name
        if waiter_name not in mapping:
            raise ValueError("Waiter does not exist: %s" % waiter_name)

        return waiter.create_waiter_with_client(
            mapping[waiter_name], model, self, loop=self._loop)