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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_thumbnail(self, instance=None, **kwargs):
 """ Sets a `thumbnail` attribute on the image field class. On thumbnail you can access name, url, path attributes """

        image_field = getattr(instance, self.name)
        if image_field:
            thumbnail_filename = _get_thumbnail_filename(image_field.name)

            thumbnail_field = ThumbnailField(thumbnail_filename, self.storage)
            setattr(image_field, 'thumbnail', thumbnail_field)