input: from typing import List
  
  def str_to_lower(string: str) -> str:
      """
      Converts a given string to its lowercase version.
  
      >>> str_to_lower("Hello World")
      'hello world'
      >>> str_to_lower("Python IS Awesome")
      'python is awesome'
      """
      new_string = ""
  
      for char in string:
          new_string += char.lower()
  
      return new_string
output:     new_string = ""
  
      for char in string:
          new_string += char.lower()
  
      return new_string