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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, image):
 """ Set the image for this file. This also caches the dimensions of the image. """

        if image:
            self._image_cache = image
            self._dimensions_cache = image.size
        else:
            if hasattr(self, '_image_cache'):
                del self._cached_image
            if hasattr(self, '_dimensions_cache'):
                del self._dimensions_cache