I've started to mass upload files from Flickr (as there seemed to be a need to upload before it starts to delete pictures). Thus, I downloaded a whole Flickr stream, sanitized names and started to upload. However, I keep on receiving messages such as this:
pywikibot.data.api.APIError: titleblacklist-forbidden: ⧼titleblacklist-custom-filename⧽ [message:{'key': 'titleblacklist-custom-filename', 'params': [' File:\\P{L}*\\.[^.]+ <reupload|errmsg=titleblacklist-custom-filename>', 'File:2017-03-18 20.57.33 (33527105145).jpg']}; line: File:\P{L}*\.[^.]+ <reupload|errmsg=titleblacklist-custom-filename>; filekey:1664nnvgt7q8.aqks42.3572532.jpg; sessionkey:1664nnvgt7q8.aqks42.3572532.jpg; invalidparameter:filename; help:See https://commons.wikimedia.org/w/api.php for API usage. Subscribe to the mediawiki-api-announce mailing list at <https://lists.wikimedia.org/mailman/listinfo/mediawiki-api-announce> for notice of API deprecations and breaking changes.]
It's really weird, as I can upload the very same file from Flickr using the built-in feature in Commons upload form and it accepts it, with exactly the very same filename. I cannot understand the regular expression provided as rationale, but I'm not actually sure it's a problem with the name.