How to upload data with files to a Flask application?

Question

I'm trying to upload a file along with some data to a Flask server using Python Requests.

Here's my code:

@app.route('/', methods=['GET', 'POST'])
def upload_file():
    if request.method == 'POST':
        temp_image = request.files['file']
        filename = secure_filename(temp_image.filename)
        temp_image.save(os.path.join(app.config['UPLOAD_FOLDER'], filename))
        return 'Success'

 url = "https://some-random-url.com/"
 files = {'file': open("shared/assets/12332.png", 'rb')}
 data = {"lobby_id": "lobby_id"}
 r = requests.post(url=url, files=files)

So this part works absolutely fine and I get <Response [200]>.

But when I include the data part, and modify my Flask part of the code to,

@app.route('/', methods=['GET', 'POST'])
def upload_file():
    if request.method == 'POST':
        temp_image = request.files['file']
        data = request.get_json(force=True)
        filename = secure_filename(temp_image.filename)
        temp_image.save(os.path.join(app.config['UPLOAD_FOLDER'], filename))
        return 'Success'

I get <Response [400]>. I'm assuming there's a mistake in the Flask section of the code but I'm unable to figure it out.