How to not repeat myself in a loop python

Question

I am learning how to use do not repat yourself principle ( https://en.wikipedia.org/wiki/Don%27t_repeat_yourself ) in Python.

See my block of code below:

        for key, value in my_dictionary.items():
            if "," in value:
                if key != value:
                    raise ValueError(f"This is my error !")
            else:
                if key != value + ",00":
                    raise ValueError(f"This is my error !")

You can see that I repeat the part raise ValueError(f"This is my error !") two times. Is it posible to use it only once? I tried to use for/else method, but I got lost. Thank you very much for help.

Answer 1

You could use

for key, value in my_dictionary.items():
    if ("," in value and key != value) or (key != value + ",00"):
        raise ValueError(f"This is my error !")
    
    # everything seems to be fine
    # do sth. useful here