:- use_module(library(http/http_digest)).
http_digest_response(+Challenge, 
+User, +Password, -Reply, +Options)/'GET'| Challenge | is a list Name(Value), normally 
from
http_parse_digest_challenge/2. 
Must contain
realm and nonce. Optionally contains
opaque.  | 
| User | is the user we want to authenticated | 
| Password | is the user's password | 
| Options | provides additional options |