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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 look_for_hdl_urls(citation_elements):
 """Looks for handle identifiers that have already been identified as urls When finding an hdl, creates a new HDL element. @param citation_elements: (list) elements to process """

    for el in citation_elements:
        if el['type'] == 'URL':
            match = re_hdl.match(el['url_string'])
            if match:
                el['type'] = 'HDL'
                el['hdl_id'] = match.group('hdl_id')
                del el['url_desc']
                del el['url_string']