Access token?

[smlbiobot]

Hi, I couldn’t figure out how to get the access token. I read the source and I see the exchange_code method but when I tried to access using:

r = api.exchange_code(API_CODE, 'http://localhost:7777/token_redirect)

it raises an error:
youtube.exceptions.YouTubeException: (400, 'invalid_request', <Response [400]>)

where API_CODE is the code I received from doing an auth request.