input: Write a function to print the length of a given string. Handle cases where the string is empty as well.
  assert print_length("")==None
  assert print_length("Python")==None
  assert print_length("Programming")==None
  assert print_length("OpenAI")==None
  assert print_length("Code")==None
output: def print_length(s):
      if s == "":
          print(0)
      else:
          print(len(s))