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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def guess_mode(self, data):
 """ Guess what type of image the np.array is representing """

        # TODO: do we want to support dimensions being at the beginning of the array?
        if data.ndim == 2:
            return "L"
        elif data.shape[-1] == 3:
            return "RGB"
        elif data.shape[-1] == 4:
            return "RGBA"
        else:
            raise ValueError(
                "Un-supported shape for image conversion %s" % list(data.shape))