def correl_model(self):
        """
        Return a correlation object. See :mod:`openquake.hazardlib.correlation`
        for more info.
        """
        correl_name = self.ground_motion_correlation_model
        if correl_name is None:  # no correlation model
            return
        correl_model_cls = getattr(
            correlation, '%sCorrelationModel' % correl_name)
        return correl_model_cls(**self.ground_motion_correlation_params)
Return a correlation object. See :mod:`openquake.hazardlib.correlation`
        for more info.