If your program is passed any invalid values, it should raise a ValueError

It is not specified what "invalid values" mean in the kata. Input validation without specification is an open-ended question, which boils down to everyone trying to read kata author's mind (which is bad, obviously).

For safety, we require that the substring must be at least two characters long, otherwise raise a ValueError.

This doesn't really add anything to the task, and should be removed IMO.

Hello! I think there are some changes that can be done:

• It might be a good idea to indicate the tolerance to errors you have, since it seems like floats must be used.
• Just as with the fun parameter, specifying the return type and semantics of the euler_sol function is a good addition.
• This is more personal, but a simple example is always welcome in these mathematical exercises.

Cheers :)

Edit: using Python's type hints is also a very good addition to make your kata much more understandable and less prone to interpretation errors.

Hi,

• :cough:
• Note: we already have tons of this kind of task, so why create one more? This adds nothing to the database... :o
• :cough-cough: :

...so no input-testing should be required.

If the list is empty or None, return 0.

=> meh...? Looks like there is a contradiction somewhere... :/

Cheers

Is this solution supposed to pass: click here

Reraising below as issue