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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 _init_taxids(taxid, taxids):
 """Return taxid set"""

        ret = set()
        if taxids is not None:
            if taxids is True:
                return True
            if isinstance(taxids, int):
                ret.add(taxids)
            else:
                ret.update(taxids)
        if taxid is not None:
            ret.add(taxid)
        if not ret:
            ret.add(9606)
            # pylint: disable=superfluous-parens
            print('**NOTE: DEFAULT TAXID STORED FROM gene2go IS 9606 (human)\n')
        return ret