human
Solve the following python programming problem given the following code:
def compose(self, digest = None, basic = None, username = None, password = None, challenge = None, path = None, method = None) : 
    assert (username and password) 
    if (basic or (not challenge)) : 
        assert (not digest) 
        userpass = ('%s:%s' % (username.strip (), password.strip ())) 
        return ('Basic %s' % userpass.encode ('base64').strip ()) 
assert (challenge and (not basic)) 
    path = (path or '/') 
    (_, realm) = challenge.split ('realm="') 
    (realm, _) = realm.split ('"', 1) 
    auth = AbstractDigestAuthHandler () 
    auth.add_password (realm, path, token, password) 
    (token, challenge) = challenge.split (' ', 1) 
    chal = parse_keqv_list (parse_http_list (challenge)) 
    class FakeRequest (object) : 
        if six.PY3 : 
            @ property 
            def full_url(self) : 
                return path 
selector = full_url 
            @ property 
            def data(self) : 
                return None 
else : 
            def get_full_url(self) : 
                return path 
get_selector = get_full_url 
            def has_data(self) : 
                return False 
def get_method(self) : 
            return (method or 'GET') 
retval = ('Digest %s' % auth.get_authorization (FakeRequest (), chal)) 
    return (retval,) 

    
    

    Fix the buggy line: auth.add_password (realm, path, token, password)
assistant
#Here is Python code to fix the buggy line: auth.

auth.add_password (realm, path, username, password)