Export the minimal state of `self` for inference in `self.path/file`. `file` can be file-like (file or buffer)

def export(self, file:PathLikeOrBinaryStream='export.pkl'):
        "Export the minimal state of `self` for inference in `self.path/file`. `file` can be file-like (file or buffer)"
        xtra = dict(normalize=self.norm.keywords) if getattr(self, 'norm', False) else {}
        try_save(self.valid_ds.get_state(**xtra), self.path, file)