input: Write a python function to get ASCII values of characters in a string.
  assert getAscii('Hello') == [72, 101, 108, 108, 111]
  assert getAscii('World') == [87, 111, 114, 108, 100]
  assert getAscii('Python') == [80, 121, 116, 104, 111, 110]
output: def getAscii(s):
      return [ord(char) for char in s]