code: def solarReturn(self, year):
          
          sun = self.getObject(const.SUN)
          date = Datetime('{0}/01/01'.format(year),
                          '00:00',
                          self.date.utcoffset)
          srDate = ephem.nextSolarReturn(date, sun.lon)
          return Chart(srDate, self.pos, hsys=self.hsys)
docs: Returns this chart's solar return for a 
          given year.