Python Creating a Function that checks if a part of a list is a number or not

Python
1

I’m trying to create a function that takes a string with letters, numbers, and other characters, and then returns a string with only numbers and question marks in it. When I run the following function with the input arrb6???4xxbl5???eee5, it returns the whole string and not just numbers. What can I do to improve my code?

def questionmarkstry(string):
    list_string = [x for x in string]
    liststringnew = []
    for letter in list_string:
        if string == "1" or "2" or "3" or "4" or "5" or "6" or "7" or "8" or "9" or "0" or "?":
            liststringnew.append(letter)
        elif string != "1" or "2" or "3" or "4" or "5" or "6" or "7" or "8" or "9" or "0" or "?":
            pass
   return liststringnew

Here is an updated version:

def questionmarkstry(string):
    list_string = [x for x in string]
    liststringnew = []
    for l in list_string:
        if l == "1" or l == "2" or l == "3" or l == "4" or l == "5" or l == "6" or l == "7" or l == "8" or l == "9" or l == "0" or l =="?":
            liststringnew.append(l)
        else:
            pass
        
    return(liststringnew)
2

That’s not how you make an if statement with multiple clauses in Python (or any other language).

You want

if test_1 or test_2 or ... or test_11:
  ...
3

I edited my code to reflect those improvements, but it still gives back the whole string instead of just numbers and question marks.

4

Please post your most recent code, as the one in your first post is still not valid syntax.

5

Yeah, you didn’t make the change I suggested. "2" is not a logical conditional. string == "2" is.

6

I have now updated the code.

7

Why is there an elif? Wouldn’t an else with no conditionals work better?

8

Thanks for the help. I have now figured out the code.

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