def __init__(self, groups=None):
        super(GroupedRequirements, self).__init__(NamedRequirements)
        self.groups = groups or self.default_groups
        self.filename = None
        self.create_default_groups()
def testName(self):
        plotter = VoltageProfilePlotter(xaxis="frac_x")
        plotter.add_electrode(self.ie_LTO, "LTO insertion")
        plotter.add_electrode(self.ce_FF, "FeF3 conversion")
        self.assertIsNotNone(plotter.get_plot_data(self.ie_LTO))
        self.assertIsNotNone(plotter.get_plot_data(self.ce_FF))