def __init__(self, data_root, is_training , input_frames="1357"):
        """
        Creates a Vimeo Septuplet object.
        Inputs.
            data_root: Root path for the Vimeo dataset containing the sep tuples.
            is_training: Train/Test.
            input_frames: Which frames to input for frame interpolation network.
        """
        self.data_root = data_root
        self.image_root = os.path.join(self.data_root, 'sequences')
        self.training = is_training
        self.inputs = input_frames

        test_fn = os.path.join(self.data_root, 'sep_testlist.txt')
        with open(test_fn, 'r') as f:
            self.testlist = f.read().splitlines()

        if self.training:
            train_fn = os.path.join(self.data_root, 'sep_trainlist.txt')
            with open(train_fn, 'r') as f:
                self.trainlist = f.read().splitlines()

            self.transforms = transforms.Compose([
                transforms.RandomCrop(256),
                transforms.RandomHorizontalFlip(0.5),
                transforms.RandomVerticalFlip(0.5),
                transforms.ColorJitter(0.05, 0.05, 0.05, 0.05),
                transforms.ToTensor()
            ])
        else:
            self.transforms = transforms.Compose([
                transforms.ToTensor()
            ])

        Creates a Vimeo Septuplet object.
        Inputs.
            data_root: Root path for the Vimeo dataset containing the sep tuples.
            is_training: Train/Test.
            input_frames: Which frames to input for frame interpolation network.
        
dataset/vimeo90k_septuplet.py