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 check_prereq(self, prereqMode = 0):
        self._exit_modes_beyond(prereqMode)
        if len(self.modeList) <= prereqMode:
            raise Exception("Attempted to enter menu when prerequist mode was not entered, expected: %d" % prereqMode)