# Using typing in Python leads to different sorts of code

> Source: <https://utcc.utoronto.ca/~cks/space/blog/python/TypeHintsDifferentCode>
> Published: 2026-05-28 08:01:59+00:00

You're probably reading this page because you've attempted to access
some part of [my blog (Wandering Thoughts)](../space/blog/) or
[CSpace](../space/), the wiki thing it's part of. Unfortunately
you're using a browser version that my anti-crawler precautions consider
suspicious, most often because it's too old (most often this applies to
versions of Chrome). Unfortunately, as of early 2025 there's a plague
of high volume crawlers (apparently in part to gather data for LLM
training) that use a variety of old browser user agents, especially
Chrome user agents. To reduce the load on
[Wandering Thoughts](../space/blog/) I'm experimenting with
(attempting to) block all of them, and you've run into this.

If this is in error and you're using a current version of your
browser of choice, you can contact me at [my current place at the
university](https://www.cs.toronto.edu/~cks/) (you should be able to work out the email address
from that). If possible, please let me know what browser you're
using and so on, ideally with its exact User-Agent string.

I am not blocking Inoreader's feed fetcher or considering it to be
too old, and it routinely fetches feeds from me. I don't know why
Inoreader is showing you this page. It is possible that they're
periodically trying to fetch feeds or pages with an old browser
HTTP User-Agent (or an actual old browser) and taking the results
of that fetch (this page) as what they should show people instead
of the results of their syndication feed fetcher agents. This is a
bad mistake today; [the results
of modern HTTP fetches depend partly on the HTTP User-Agent used](/~cks/space/blog/web/HTTPResultsAndUserAgents).

Much like Inoreader, Feedly is periodically fetching my syndication
feeds with a fake, old browser HTTP User-Agent header, which fails,
and is then grimly latching on to the results for their actual feed
fetching with their regular Feedly HTTP User-Agent. There is nothing
I can do about this; you should contact Feedly support, if you can
find them. See [this
comment of mine in Wandering Thoughts](https://utcc.utoronto.ca/~cks/space/blog/web/FeedReaderErrorsProblem?showcomments#cks-20260215115901) for more details.

Due to an ongoing attack, you may need to change
[the
"User Agent Brand Masking" setting](https://help.vivaldi.com/desktop/miscellaneous/user-agent-brand-masking/) so that your Vivaldi identifies
itself as Vivaldi, instead of Google Chrome. This applies to even
the current version of Vivaldi.

You may be seeing this through archive.today, archive.ph, archive.is,
and so on. Unfortunately, archive.* crawls pages to archive in a way that
is impossible to distinguish from malicious actors. They use old Chrome
User-Agent values, crawl from IP address blocks that are widely distributed
and not clearly identified as theirs, and some of their IP addresses have
falsified reverse DNS entries that claim they are googlebot IP addresses
(which is something that is normally done only by quite bad actors). I
suggest that you use archive.org, which is a better behaved archival
crawler and can crawl [my blog (Wandering Thoughts)](../space/blog/).