Function format

crates/vm/src/stdlib/builtins.rs:612–618

(
        value: PyObjectRef,
        format_spec: OptionalArg<PyStrRef>,
        vm: &VirtualMachine,
    )

    #[pyfunction]
    fn format(
        value: PyObjectRef,
        format_spec: OptionalArg<PyStrRef>,
        vm: &VirtualMachine,
    ) -> PyResult<PyStrRef> {
        vm.format(&value, format_spec.unwrap_or(vm.ctx.new_str("")))
    }

    #[pyfunction]
    fn getattr(