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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_nest_alts_are_valid_alts(nest_spec, list_elements, all_ids):
 """ Ensures that the alternative id's in `nest_spec` are all in the universal choice set for this dataset. Raises a helpful ValueError if they are not. Parameters nest_spec : OrderedDict, or None, optional. Keys are strings that define the name of the nests. Values are lists of alternative ids, denoting which alternatives belong to which nests. Each alternative id must only be associated with a single nest! Default == None. list_elements : list of ints. Each element should correspond to one of the alternatives identified as belonging to a nest. all_ids : list of ints. Each element should correspond to one of the alternatives that is present in the universal choice set for this model. Returns ------- None. """

    invalid_alt_ids = []
    for x in list_elements:
        if x not in all_ids:
            invalid_alt_ids.append(x)
    if invalid_alt_ids != []:
        msg = "The following elements are not in df[alt_id_col]: {}"
        raise ValueError(msg.format(invalid_alt_ids))

    return None