human
Solve the following python programming problem given the following code:
def add_to(search_term, all_users, country_stub, city = None) : 
    def users_from(location) : 
        complete = False 
        page = 1 
        users = [] 
        order = 'asc' 
        while (not complete) : 
            if (page > 10) : 
                if (order == 'desc') : 
                    complete = True 
                    continue 
order = 'desc' 
                page = 1 
req = requests.get (('https://api.github.com/legacy/user/search/location:%s' % location), headers = headers, params = { 
                'start_page' : page, 
                'sort' : 'joined', 
                'order' : order, 
}, auth = TOKEN_AUTH) 
            page += 1 
            try : 
                jsusers = json.loads (req.content).get ('users') 
                if (not len (jsusers)) : 
                    complete = True 
                    continue 
users += jsusers 
except : 
                logger.warning ('Failed to parse JSON:') 
                logger.warning (req.content) 
                complete = True 
return users 
json_users = users_from (search_term) 
    if (not len (city)) : 
        return 
for user in json_users : 
        logger.info (('FOUND -- %s -- %s' % (user.get ('username'), user.get ('location')))) 
        user.update ({ 
            'country' : country_stub, 
            'city' : city, 
}) 
        all_users.append (user) 

    
    

    Fix the buggy line: if (not len (city)) :
assistant
#Here is Python code to fix the buggy line: if (not len (city)) :
.

if (not len (json_users)) :