def METHOD_NAME(self):
    api = self.parse("""
        HPy_ID(0) HPy h_None;
        HPy_ID(1) HPy HPy_Add(HPyContext *ctx, HPy h1, HPy h2);
    """)
    got = autogen_ctx_h(api).generate()
    exp = """
        struct _HPyContext_s {
            const char *name; // used just to make debugging and testing easier
            void *_private;   // used by implementations to store custom data
            int abi_version;
            HPy h_None;
            HPy (*ctx_Add)(HPyContext *ctx, HPy h1, HPy h2);
        };
    """
    assert src_equal(exp, got)