In [14]: import urllib
In [15]: urllib.unquote("%3a")
Out[15]: ':'
In [16]: urllib.unquote("%2f")
Out[16]: '/'
In [17]: urllib.unquote("%3f")
Out[17]: '?'
In [18]: urllib.unquote("%26")
Out[18]: '&'
In [19]: urllib.unquote("%25")
Out[19]: '%'
In [20]: urllib.unquote("%3d")
Out[20]: '='
In [21]: urllib.unquote("%2b")
Out[21]: '+'