我可以接收到正确的对象，但是无法用状态值更新的对象来更新上下文值

在：

const Context = createContext({
  theme: dark,
  toggleTheme: () => {},
});

我想使主题：dark，变为，主题：defaultTheme，使用 useState 修改的动态值

import React, { createContext, useState } from 'react';

import light from '../themes/light';
import dark from '../themes/dark';

const Context = createContext({
  theme: dark,
  toggleTheme: () => {},
});

export default Context;

export function ThemeContextProvider({ children }) {
  const [defaultTheme, setDefaultTheme] = useState(dark);

  function toggleTheme() {
    setDefaultTheme(defaultTheme === dark ? light : dark);
  }
  
  return (
    <Context.Provider value={{ theme, toggleTheme }}>
    {children}
    </Context.Provider>
  )
}