Error in my code

[TumbleR]

Hello everyone,
I am working on my school homework that is quite easy for some professional, but I have troubles with few things that I tried to change but obviously I can't make them work.

p=[]
def number():
    c=1
    try:   
        x=int(input("Insert integer number:"))
        p.append(x)
        for z in p:
            nn=p.sort(p) #nn=new number
        print(p,"->",nn)
        
    except ZeroDivisionError: 
        print("You cant divide by Zero")
        c=0
    except ValueError:
        print("You didn't insert integer number")
        c=0
    return c

while c!=0:
    number()

The point of this exercise is to insert numbers until we insert 0, than every inserted number - every digit of this number sort in order from the biggest to smallest.

After making this, the program tells me

Output:
1# name "c" is not defined - when I define c as 1 (c=1), next problem income
2# File "/Users/adam/Desktop/python/kod2.py", line 12, in cisla
    nc=p.sort(z)
    TypeError: sort() takes no positional arguments

- after 2nd problem I tried to delete "p" from parentheses and than my program did this:

Output:
Insert integer number: --I inserted 23---
program did this:
[23] --> None

Does anyone have any solution how to solve this? I tried almost everything...