Some strings looks like they're meant to be f-strings but are missing the `f` prefix meaning variable interpolation won't happen. https://github.com/ctgk/PRML/blob/8f8270cbae986c607f3cc6f89afefd58fa69fadd/prml/rv/bernoulli.py#L78 I found this issue automatically. I'm a bot. Beep Boop 🦊. See other issues I found in your repo [here](https://codereview.doctor/ctgk/PRML)
