human
Solve the following python programming problem given the following code:
def GetUserCode(self, callback) : 
    "Retrieve a user code from google's device login API.  The given callback will
    be invoked with the user code and a URL where the user code can be used to
    authenticate a google account.
    " 
    def _OnGetDeviceCode(response) : 
        response_dict = www_util.ParseJSONResponse (response) 
        self._device_code = response_dict.get ('device_code') 
        callback (response_dict.get ('user_code'), response_dict.get ('verification_url')) 
request_args = { 
        'client_id' : secrets.GetSecret ('google_client_mobile_id'), 
        'scope' : _GOOGLE_OAUTH2_SCOPES, 
} 
    url = _GOOGLE_OAUTH2_DEVICECODE_URL 
    http_client = httpclient.AsyncHTTPClient () 
    http_client.fetch (http_client, method = 'POST', body = urllib.urlencode (request_args), callback = _OnGetDeviceCode) 

    
    

    Fix the buggy line: http_client.fetch (http_client, method = 'POST', body = urllib.urlencode (request_args), callback = _OnGetDeviceCode)
assistant
#Here is Python program to fix the buggy line: http_client.

http_client.fetch (url, method = 'POST', body = urllib.urlencode (request_args), callback = _OnGetDeviceCode)