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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 process_url(self, page_num, page_size, url):
 """ When slicing, remove the per_page and page parameters and pass to requests in the params dict """

        params = dict()
        if page_num is not None:
            url = re.sub('page=\d+', '', url)
            params['page'] = page_num
        if page_size is not None:
            url = re.sub('per_page=\d+', '', url)
            params['per_page'] = page_size
        return params, url