docs: def _timedelta_from_elements(elements):
      """
      Return a timedelta from a dict of date elements.
  
      Accepts a dict containing any of the following:
        - years
        - months
        - days
        - hours
        - minutes
        - seconds
  
      If years and/or months are provided, it will use a naive calcuation
      of 365 days in a year and 30 days in a month.
      """
      days = sum((
          elements['days'],
          _months_to_days(elements.get('months', 0)),
          _years_to_days(elements.get('years', 0))
      ))
  
      return datetime.timedelta(days=days,
                                hours=elements.get('hours', 0),
                                minutes=elements.get('minutes', 0),
                                seconds=elements.get('seconds', 0))