human
Solve the following python programming problem given the following code:
def RecordSubscription(client, obj_store, user_id, device_id, request, callback) : 
    'Records an external subscription.' 
    def _OnRecord(verify_response, op) : 
        callback ({ 
            'subscription' : Subscription.CreateFromITunes (user_id, verify_response).MakeMetadataDict (), 
}) 
def _OnVerify(environment, verify_response) : 
        if ((environment == 'prod') and (verify_response.GetStatus () == VerifyResponse.SANDBOX_ON_PROD_ERROR)) : 
            ITunesStoreClient.Instance ('dev').VerifyReceipt (receipt_data, partial (_OnVerify, 'dev')) 
            return 
if (not verify_response.IsValid ()) : 
            logging.warning ('record_subscription: invalid signature.
request: %r', request) 
            raise web.HTTPError (400, 'invalid receipt signature') 
if (environment == 'prod') : 
            op_request = { 
                'headers' : request ['headers'], 
                'user_id' : user_id, 
                'verify_response_str' : verify_response.ToString (), 
} 
            Operation.CreateAndExecute (client, user_id, device_id, 'Subscription.RecordITunesTransactionOperation', op_request, partial (_OnRecord, verify_response)) 
else : 
            callback ({ 
                'subscription' : Subscription.CreateFromITunes (user_id, verify_response).MakeMetadataDict (), 
}) 
receipt_data = base64.b64decode (device_id ['receipt_data']) 
    ITunesStoreClient.Instance ('prod').VerifyReceipt (receipt_data, partial (_OnVerify, 'prod')) 

    
    

    Fix the buggy line: receipt_data = base64.b64decode (device_id ['receipt_data'])
assistant
#Here is Python code to fix the buggy line: receipt_data = base64.

receipt_data = base64.b64decode (request ['receipt_data'])