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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 boundary_map(self):
 """ Computes the boundary pixels in the image and sets them to nonzero values. Returns ------- :obj:`BinaryImage` binary image with nonzeros on the boundary of the original image """

        # compute contours
        contours = self.find_contours()

        # fill in nonzero pixels
        new_data = np.zeros(self.data.shape)
        for contour in contours:
            new_data[contour.boundary_pixels[:, 0].astype(np.uint8),
                     contour.boundary_pixels[:, 1].astype(np.uint8)] = np.iinfo(np.uint8).max
        return BinaryImage(new_data.astype(np.uint8), frame=self.frame)