cj = cookielib.CookieJar()
op = urllib2.build_opener(urllib2.HTTPCookieProcessor(cj)
op.open(url, data)

>>> import cookielib
>>> cj = cookielib.CookieJar()
>>> c = cookielib.Cookie('1', 'abc', 'defg', '80', '80', 'hijk', 'hijk', 'hijk', 'hijk', '/path', '/path', '1', '1', 'abc', 'defg', 'defg', 'hijk')
>>> c
Cookie(version=1, name='abc', value='defg', port='80', port_specified='80', domain='hijk', domain_specified='hijk', domain_initial_dot='hijk', path='hijk', path_specified='/path', secure='/path', expires=1, discard='1', comment='abc', comment_url='defg', rest='defg', rfc2109='hijk')
>>> cj.set_cookie(c)
>>> cj
<cookielib.CookieJar[Cookie(version=1, name='abc', value='defg', port='80', port_specified='80', domain='hijk', domain_specified='hijk', domain_initial_dot='hijk', path='hijk', path_specified='/path', secure='/path', expires=1, discard='1', comment='abc', comment_url='defg', rest='defg', rfc2109='hijk')]>
>>> print cj
<cookielib.CookieJar[<Cookie abc=defg for hijk:80hijk>]>
>>> cj._cookies
{'hijk': {'hijk': {'abc': Cookie(version=1, name='abc', value='defg', port='80', port_specified='80', domain='hijk', domain_specified='hijk', domain_initial_dot='hijk', path='hijk', path_specified='/path', secure='/path', expires=1, discard='1', comment='abc', comment_url='defg', rest='defg', rfc2109='hijk')}}}
>>>