docs: def merge_datetime(date, time='', date_format='%d/%m/%Y', time_format='%H:%M'):
      """Create ``datetime`` object from date and time strings."""
      day = datetime.strptime(date, date_format)
      if time:
          time = datetime.strptime(time, time_format)
          time = datetime.time(time)
          day = datetime.date(day)
          day = datetime.combine(day, time)
      return day