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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 _ensure_tuple_or_list(arg_name, tuple_or_list):
 """Ensures an input is a tuple or list. This effectively reduces the iterable types allowed to a very short whitelist: list and tuple. :type arg_name: str :param arg_name: Name of argument to use in error message. :type tuple_or_list: sequence of str :param tuple_or_list: Sequence to be verified. :rtype: list of str :returns: The ``tuple_or_list`` passed in cast to a ``list``. :raises TypeError: if the ``tuple_or_list`` is not a tuple or list. """

    if not isinstance(tuple_or_list, (tuple, list)):
        raise TypeError(
            "Expected %s to be a tuple or list. "
            "Received %r" % (arg_name, tuple_or_list)
        )
    return list(tuple_or_list)