python get the length of a string and go backwards and stop at character code example

Example: reverse string method python

#linear

def reverse(s): 
  str = "" 
  for i in s: 
    str = i + str
  return str

#splicing
'hello world'[::-1]

#reversed & join
def reverse(string): 
    string = "".join(reversed(string)) 
    return string