Retrieve call transcript using python

Hi! I'm new to Gong and I'm trying to use python and the API to retrieve our available data.

I managed to get basic information on the calls iterating through https://api.gong.io/v2/calls, using the request package. Now I want to get all of the call's transcripts and details and I can't seem to manage.

This is what I've tried:

url =  'https://api.gong.io/v2/calls/transcript?callIds=<CALL_ID>'
requests.get(url, auth=(<ACCESS_KEY>, <GONG_SECRET_KEY>)).json()

this throws this error:

{'requestId': <REQUEST_ID>, 'errors': ['Bad request']}

Could you help me figure out what I'm doing wrong?

Thank you!