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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 apply(self, fn):
 """ Apply an arbitrary function to ANTsImage. Args ---- fn : python function or lambda function to apply to ENTIRE image at once Returns ------- ANTsImage image with function applied to it """

        this_array = self.numpy()
        new_array = fn(this_array)
        return self.new_image_like(new_array)