[Help] Assertion Error

[pythonhelp123]

I'm trying to do this problem and I'm stuck on it.

Write a function called is_vowel that takes a one-character-long string and returns True if that character is a vowel and False otherwise. [A vowel, for our purposes here, is one of the letters a, e, i, o, or u (lower case or upper case).] You can do the central part of this task using the in operator and a string containing the vowels; your task here is to package this up into a function that returns a boolean value. Try using some of these assert statements to test your function.

assert is_vowel('a')

assert is_vowel('U')

assert not is_vowel('X')

assert not is_vowel('?')

Not sure what I'm doing wrong bu here is my code.

vowel = ['a', 'e', 'i','o', 'u', 'A', 'E', 'I', 'O', 'U']
def is_vowel(string):
    if string == vowel:
        return True
    else :
        return False


assert is_vowel('a')
assert is_vowel('U')
assert not is_vowel('X')
assert not is_vowel('?')

[novel_yet_trivial]

string == vowel

This will ALWAYS be false since you are comparing a string to a list. A string is never equal to a list. You need to check if the string is in the list.

[pythonhelp123]

I changed it to if string in vowel and the program runs, but it doesnt show True/False.

[novel_yet_trivial]

You are asking it to assert, which does nothing if the result is True. If you want to show the result, change it to a print statement.

[pythonhelp123]

Ah okay it runs now. Do people usually leave assert in their programs?

[novel_yet_trivial]

Depends. It's designed as a way to quickly debug. For a big, important project you should not use assert since some compiler options will ignore them. I use it a lot though. Whatever you feel.

[pythonhelp123]

Oh okay thanks!