python使用urllib2模块获取gravatar头像实例

# import code for encoding urls and generating md5 hashes
import urllib2, hashlib

# Make response slow if verify whether default avatar or not.
# So let js do it, see `/static/js/article.js`.
def gravatar_url(email, size=40, verify_default=False):
"""Construct the gravatar url."""
gravatar_url = ''.join(['http://www.gravatar.com/avatar/',
hashlib.md5(email.lower()).hexdigest(), '?s=%d' % size])
# if default return None
if (verify_default):
gravatar_url += '&d=404'
try:
urllib2.urlopen(gravatar_url)
except urllib2.URLError, e:
return None
return gravatar_url

if __name__ == '__main__':
import webbrowser as wb
for email in ['xxx@gmail.com']:
url = gravatar_url(email)
print(url)
if url:
wb.open(url)