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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 save_image(self, cat, img, data):
 """Saves a new image."""

        filename = self.path(cat, img)
        mkdir(filename)
        if type(data) == np.ndarray:
            data = Image.fromarray(data).convert('RGB')
        data.save(filename)