docs: def section(self, dept, course_number, sect_number):
          """Return a single section object for the given section. All arguments
          should be strings. Throws a `ValueError` if the section is not found.
  
          >>> lgst101_bfs = r.course('lgst', '101', '301')
          """
          section_id = dept + course_number + sect_number
          sections = self.search({'course_id': section_id})
          try:
              return next(sections)
          except StopIteration:
              raise ValueError('Section %s not found' % section_id)