urllib.error.HTTPError: HTTP Error 403: Forbidden

[Make42]

I would like to download all papers of https://epubs.siam.org/doi/book/10.1137/1.9781611976700 and get them as a single PDF, but I get the error

$ python pd.py --user_agent "Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:56.0) Gecko/20100101 Firefox/56.0" -u https://epubs.siam.org/doi/book/10.1137/1.9781611976700 --store
Pre-Parse conference webpage
Traceback (most recent call last):
[...]
  File "/Development/Anaconda-Python-Distribution/miniconda3/envs/paperDownloader/lib/python3.9/urllib/request.py", line 641, in http_error_default
    raise HTTPError(req.full_url, code, msg, hdrs, fp)
urllib.error.HTTPError: HTTP Error 403: Forbidden

What can I do about this?

[fjxmlzn]

Sorry for the delay. I just posted a commit to fix this issue. I locally tested the URL you gave and it should work now. Please let me know if you experience any additional issues.