You can use find_all in the following way to find every a element that has an href attribute, and print each one:
from BeautifulSoup import BeautifulSoup
html = '''<a href="some_url">next</a>
<span class="class"><a href="another_url">later</a></span>'''
soup = BeautifulSoup(html)
for a in soup.find_all('a', href=True):
print "Found the URL:", a['href']
The output would be:
Found the URL: some_url
Found the URL: another_url
Note that if you're using an older version of BeautifulSoup (before version 4) the name of this method is findAll. In version 4, BeautifulSoup's method names were changed to be PEP 8 compliant, so you should use find_all instead.
If you want all tags with an href, you can omit the name parameter:
href_tags = soup.find_all(href=True)