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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 _netid_category_url(netid, category_codes):
 """ Return UWNetId resource for provided netid and category code or code list """

    return "{0}/{1}/category/{2}".format(
        url_base(), netid,
        (','.join([str(n) for n in category_codes])
         if isinstance(category_codes, (list, tuple))
         else category_codes))