keep getting this error

[larschri15]

i get the hole time this error:

Traceback (most recent call last):
File "C:\Users\larss\Downloads\thingiscrape-master\thingiscrape-master\thingiscrape.py", line 324, in
popular(args.popular_true)
File "C:\Users\larss\Downloads\thingiscrape-master\thingiscrape-master\thingiscrape.py", line 94, in popular
generic_search(sort_type="popular", n_pages=n_pages)
File "C:\Users\larss\Downloads\thingiscrape-master\thingiscrape-master\thingiscrape.py", line 76, in generic_search
rest_url += access_keyword + api_token + rest_keywords["pages"] + str(idx + 1)
TypeError: can only concatenate str (not "NoneType") to str