code: def prompt_4_overwrite(filename, force_write, input = None):
      
      if not os.path.exists(filename) or force_write:
          return True
      return prompt_4_yes_no('File \'{}\' already exists. Do you want to overwrite it'.format(filename), input = input)
docs: Prompt whether the file should be overwritten
  
      :param filename:                    Name of the file about to be written
      :param force_write:                 Skip confirmation prompt if this flag is set
      :param input:                       Used for unit testing
  
      :return:                            Boolean whether file write operation is allowed