Declaring available dimensions like this is not mandatory,
         but nice, especially if they differ from dataset to dataset.

         If you are using a built in datatype, you can specify the dialect
         you are expecting, to have values normalized. This scraper will
         look for Swedish month names (e.g. 'Januari'), but return them
         according to the Statscraper standard ('january').

def _fetch_dimensions(self, dataset):
        """ Declaring available dimensions like this is not mandatory,
         but nice, especially if they differ from dataset to dataset.

         If you are using a built in datatype, you can specify the dialect
         you are expecting, to have values normalized. This scraper will
         look for Swedish month names (e.g. 'Januari'), but return them
         according to the Statscraper standard ('january').
        """
        yield Dimension(u"region",
                        label="municipality or county",
                        datatype="region",
                        dialect="arbetsmiljoverket")
        yield Dimension(u"period",
                        label="Year or month")