'Return a GDAL SpatialReference object.'

@property
def srs(self):

    if hasattr(self, '_srs'):
        return self._srs.clone()
    else:
        try:
            self._srs = gdal.SpatialReference(self.wkt)
            return self.srs
        except Exception as e:
            msg = e
        try:
            self._srs = gdal.SpatialReference(self.proj4text)
            return self.srs
        except Exception as e:
            msg = e
        raise Exception(('Could    not    get    OSR    SpatialReference    from    WKT:    %s\nError:\n%s' % (self.wkt, msg)))
