    def _gen_exec_key(self, shape):
        """rendering shape info"""
        return self.exec_key_template.render(
            x_dim0=shape[0],
            x_dim1=shape[1],
            x_dim2=shape[2],
            x_dim3=shape[3],
        ).replace("\n", "")
rendering shape info
python/aitemplate/compiler/ops/attention/flash_attention.py