Error in detect.py when crop_mode == 'list'

[Coco Stiff]

I've been having an error in detect.py for list mode. The code tries to run 

        images_windows = [

            (ix, inputs.iloc[np.where(inputs.index == ix)][COORD_COLS].values)

            for ix in inputs.index.unique()

        ]

However, inputs.index.unique() returns an attribute error. I've been using a .txt file, so inputs is a list - that makes index a built in function, and unique() won't work.

I'm not sure if I've imported something incorrectly, but I haven't been able to find documentation for this type of use anywhere which makes me think it's a bug.