Python's standard urllib and urlparse modules provide a number of URL manipulation functions, but using these functions to perform common URL manipulations proves tedious. Furl makes manipulating URLs simple.
Furl is Unlicensed in the public domain so you can build amazing things.
Query arguments are easy. Really easy.
>>> from furl import furl
>>> f = furl('http://www.google.com/?one=1&two=2')
>>> f.args['three'] = '3'
>>> del f.args['one']
>>> f.url
'http://www.google.com/?two=2&three=3'
Or use furl's inline modification methods.
>>> furl('http://www.google.com/?one=1').add({'two':'2'}).url
'http://www.google.com/?one=1&two=2'
>>> furl('http://www.google.com/?one=1&two=2').set({'three':'3'}).url
'http://www.google.com/?three=3'
>>> furl('http://www.google.com/?one=1&two=2').remove(['one']).url
'http://www.google.com/?two=2'
Encoding is handled for you.
>>> f = furl('http://www.google.com/')
>>> f.path = 'some encoding here'
>>> f.args['and some encoding'] = 'here, too'
>>> f.url
'http://www.google.com/some%20encoding%20here?and+some+encoding=here,+too'
Fragments have a path and a query, too.
>>> f = furl('http://www.google.com/')
>>> f.fragment.path.segments = ['two', 'directories']
>>> f.fragment.args = {'one':'argument'}
>>> str(f)
'http://www.google.com/#two/directories?one=argument'
See more furl magic and examples in furl's API document, API.md.
Installing furl with pip is easy.
$ pip install furl