Returns GDALGrid object of GSSHA model bounds

        Paramters:
            use_mask(bool): If True, uses watershed mask. Otherwise, it uses the elevaiton grid.

        Returns:
            GDALGrid

def getGrid(self, use_mask=True):
        """
        Returns GDALGrid object of GSSHA model bounds

        Paramters:
            use_mask(bool): If True, uses watershed mask. Otherwise, it uses the elevaiton grid.

        Returns:
            GDALGrid

        """
        grid_card_name = "WATERSHED_MASK"
        if not use_mask:
            grid_card_name = "ELEVATION"

        return self.getGridByCard(grid_card_name)