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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 set_image(self, user, image_path):
 """Sets a custom image for the game. `image_path` should refer to an image file on disk"""

        _, ext = os.path.splitext(image_path)
        shutil.copy(image_path, self._custom_image_path(user, ext))