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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 map_url_to_cache_id(self, url):
 """use of the url resource location as cached id e.g.: ``<domain>/foo/bar/a.html => <base>/domain/foo/bar/a.html`` - map the url to local file :param url: :type url: :return: :rtype: """

        base, _ = self.get_domain_home_from_url(url)

        if base == '':
            # invalid url
            _sub_page = ''
        elif base == url or base + '/' == url:
            # homepage
            _sub_page = 'homepage'
        else:
            # sub page
            _sub_page = url.replace(base, '').split('/')
            _sub_page = '/'.join([x for x in _sub_page if x])

        if _sub_page:
            full_name = os.path.join(self.cache['site_raw'], _sub_page)
            return full_name
        else:
            return _sub_page