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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 palettize(self, colormap):
 """Palettize the current image using `colormap`. .. note:: Works only on "L" or "LA" images. """


        if self.mode not in ("L", "LA"):
            raise ValueError("Image should be grayscale to colorize")

        l_data = self.data.sel(bands=['L'])

        def _palettize(data):
            # returns data and palette, only need data
            return colormap.palettize(data)[0]

        new_data = l_data.data.map_blocks(_palettize, dtype=l_data.dtype)
        self.palette = tuple(colormap.colors)

        if self.mode == "L":
            mode = "P"
        else:
            mode = "PA"
            new_data = da.concatenate([new_data, self.data.sel(bands=['A'])], axis=0)

        self.data.data = new_data
        self.data.coords['bands'] = list(mode)