Describe the bug

Since an update earlier this afternoon, the dark theme fails to load and the following error pops in the console:

Uncaught TypeError: pydocthemeDark is null

To Reproduce

1. With a dark theme-enabled browser, go to https://docs.python.org/3/Using the theme switch after loading the page is a valid test case too
2. Assert dark theme hasn't loaded
3. Check Web console

Expected behavior

Dark theme loaded

URL to the issue

https://docs.python.org/3/

Relevant log output

Uncaught TypeError: pydocthemeDark is null
    activateTheme https://docs.python.org/3/_static/themetoggle.js:19
    <anonymous> https://docs.python.org/3/_static/themetoggle.js:24