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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 inpaint(self):
 """ Replace masked-out elements in an array using an iterative image inpainting algorithm. """


        import inpaint
        filled = inpaint.replace_nans(np.ma.filled(self.raster_data, np.NAN).astype(np.float32), 3, 0.01, 2)
        self.raster_data = np.ma.masked_invalid(filled)