Making a PATCH method request with a file to Common Data Service

I'm trying to create a Python script which can use the PATCH method to upload a file into MS's Common data service. I'm successfully making GET, POST, PATCH, and DELETE calls with simple data, but have so far been unable to configure it so that I can upload a file.

I've been using the Requests library for Python, with the requests.patch function in order to try updating the data. I'm attempting to upload a .csv file into the field, the file which i'm uploading has a filesize of 1kb.

If I upload the data directly into the common data service through the in-built data interface, my browser is able to correctly make a PATCH call. I've attempted to copy the call as closely as I can, but have had zero success.

File field in common data service

PATCH call in web browser

What is the correct way to make a PATCH request with a file to Microsoft's Common data service?

Made a mistake with the url in my request - I had missed out which field I was uploading data to

Incorrect URL: 
https://90g9j3gf.crm4.dynamics.com/api/data/v9.0/test_entity(34cd854c-1175-4778-bf95-e1ce12dea3b0)

Corrected URL: 
https://90g9j3gf.crm4.dynamics.com/api/data/v9.0/test_entity(34cd854c-1175-4778-bf95-e1ce12dea3b0)/test_field

The code I used to make the request:

Import requests

http_headers = {
  'Authorization': 'Bearer ' + token['access_token'],
  'Content-Type': 'application/octet-stream',
  'x-ms-file-name': 'test.csv'
}
filedata = open("project-folder\\test.csv", "rb")
patch_req = requests.patch(
  url, # My URL is defined elsewhere
  headers=http_headers,
  data=filedata
)

This now works correctly for me