docs: def _fetch_dimensions(self, dataset):
          """ Iterate through semesters, counties and municipalities.
          """
          yield Dimension(u"school")
          yield Dimension(u"year",
                          datatype="year")
          yield Dimension(u"semester",
                          datatype="academic_term",
                          dialect="swedish")  # HT/VT
          yield Dimension(u"municipality",
                          datatype="year",
                          domain="sweden/municipalities")