'Rate Limit Exceeded'

[ucb-pb]

I keep getting the error:

Traceback (most recent call last):
  File "download_collection_album.py", line 35, in <module>
    collection_main()
  File "download_collection_album.py", line 22, in collection_main
    get_collections(args.collection_id, args.size, args.curated)
  File "download_collection_album.py", line 9, in get_collections
    collection, s = get_response(COLLECTION_URL + 'curated/' + cid, {'client_id': ACCESS_KEY})
  File "/Users/una/Documents/GitHub/unsplash-album-downloader/download_user_album.py", line 37, in get_response
    data = json.loads(r.content.decode('utf-8'))
  File "/Library/Developer/CommandLineTools/Library/Frameworks/Python3.framework/Versions/3.7/lib/python3.7/json/__init__.py", line 348, in loads
    return _default_decoder.decode(s)
  File "/Library/Developer/CommandLineTools/Library/Frameworks/Python3.framework/Versions/3.7/lib/python3.7/json/decoder.py", line 337, in decode
    obj, end = self.raw_decode(s, idx=_w(s, 0).end())
  File "/Library/Developer/CommandLineTools/Library/Frameworks/Python3.framework/Versions/3.7/lib/python3.7/json/decoder.py", line 355, in raw_decode
    raise JSONDecodeError("Expecting value", s, err.value) from None
json.decoder.JSONDecodeError: Expecting value: line 1 column 1 (char 0)

Printing the contents of the response in download_user_album.get_response gives the message b'Rate Limit Exceeded'