Palindrome

#Lo so, non era richiesto nell'esercizio ma mi stavo divertendo.

def palindrome2(s):
#@param:
#   s: str;
#   return: bool;
    if len(s)<2:
        return True
    if len(s)%2==0:
        if s[-1+len(s)//2]==s[len(s)//2]:
            newS = s[:-1+len(s)//2]+s[1+len(s)//2:]
            return palindrome2(newS)
        else: return False
    elif len(s)%2!=0:
        newS = s[:len(s)//2]+s[1+len(s)//2:]
        return palindrome2(newS)
    else: return False

def palindromeSentence(string):
#@param:
#   string: str;
#   return: bool;
    s = prepareString(string)
    return palindrome2(s)

def reverse(string):
#@param:
#   string: str;
#   return: str;
    s = ""
    lenght = len(string) -1
    for i in range(lenght,-1,-1):
        s += string[i]
    return s

def prepareString(string):
#@param:
#   string: str;
#   return: str;
    s = ""
    for i in range(0,len(string)):
        if string[i].isdigit() or string[i].isalpha():
            s += string[i]
    s = s.lower()
    return s

def test():
    from random import randint
    r = ""
    print("Test for string lenght 0, expected True.\nResult:",palindrome2(r))
    r = str(randint(0,9))
    print("\nTest for string lenght 1, expected True.\nstring:",r,"\nResult:",palindrome2(r))
    r = randint(1000,100000)
    r = str(r) + reverse(str(r))
    print("\nTest for string random lenght (from 8 to 12 digits), expected True.\nstring:",r,"\nResult:",palindrome2(r))
    r = r+" "+r+", "+r+"!"
    print("\nTest for full sentence random lenght, expected True.\nstring:",r,"\nResult:",palindromeSentence(r))