Clone and pip install this, or put it somewhere such that the directory base16 is in (or at least is symlinked from) your PYTHONPATH.

Then import your preferred theme using importlib:

theme = importlib.import_module('base16.base16-default-dark')

Here is a complete example that configures ipython with default-dark:

theme = importlib.import_module('base16.base16-default-dark')
c.TerminalInteractiveShell.highlighting_style = theme.Base16Style
c.TerminalInteractiveShell.highlighting_style_overrides = theme.overrides

This is how it looks side-to-side with vim base16:

I strived to make prompt-toolkit themes resemble vim themes as much as possible, but not all syntax categories of vim are present in prompt-toolkit.

That's it!