def a_urls(html):
    '''
    return normalized urls found in the 'a' tag
    '''
    soup = BeautifulSoup(html, 'lxml')
    for node in soup.find_all('a'):
        try:
            href = node['href']
        except __HOLE__:
            continue
        yield norm_url(href)
dataset/ETHPy150Open dossier/dossier.models/dossier/models/features/basic.py/a_urls