input: Write a python function to randomly scramble the characters in a string.
  assert set(scrambleString("Hello")) == set("Hello")
  assert set(scrambleString("World")) == set("World")
  assert set(scrambleString("Python")) == set("Python")
output: import random
  
  def scrambleString(s):
      s_list = list(s)
      random.shuffle(s_list)
      return ''.join(s_list)