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 __init__(self, root, transforms=None):

        super().__init__(root=root)
        self.transforms = transforms

        self._flow_list = []
        self._image_list = []