code: def _iso_info(iso_year, iso_week):
      "Give all the iso info we need from one calculation"
      prev_year_start = _iso_year_start(iso_year-1)
      year_start = _iso_year_start(iso_year)
      next_year_start = _iso_year_start(iso_year+1)
      first_day = year_start + dt.timedelta(weeks=iso_week-1)
      last_day = first_day + dt.timedelta(days=6)
      prev_year_num_weeks = ((year_start - prev_year_start).days) // 7
      year_num_weeks = ((next_year_start - year_start).days) // 7
      return (first_day, last_day, prev_year_num_weeks, year_num_weeksf _iso_info(iso_year, iso_week):
      "Give all the iso info we need from one calculation"
      prev_year_start = _iso_year_start(iso_year-1)
      year_start = _iso_year_start(iso_year)
      next_year_start = _iso_year_start(iso_year+1)
      first_day = year_start + dt.timedelta(weeks=iso_week-1)
      last_day = first_day + dt.timedelta(days=6)
      prev_year_num_weeks = ((year_start - prev_year_start).days) // 7
      year_num_weeks = ((next_year_start - year_start).days) // 7
      return (first_day, last_day, prev_year_num_weeks, year_num_weeks)
docs: Give all the iso info we need from one calculation