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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 _filter_link_tag_data(self, source, soup, data, url):
 """This method filters the web page content for link tags that match patterns given in the ``FILTER_MAPS`` :param source: The key of the meta dictionary in ``FILTER_MAPS['link']`` :type source: string :param soup: BeautifulSoup instance to find meta tags :type soup: instance :param data: The response dictionary to manipulate :type data: (dict) :param url: URL used for making an absolute url :type url: string """

        link = FILTER_MAPS['link'][source]

        html = soup.find_all('link', {link['key']: link['pattern']})

        if link['type'] == 'url':
            for line in html:
                data['url'] = line.get('href')
        else:
            for line in html:
                data['images'].append({
                    'src': urljoin(url, line.get('href')),
                    'type': link['type'],
                })