first declare a Context
import Father from "./Father"
const ThemeContext = React.createContext()
<ThemeContext.Provider value={{color:"red"}}>
<Father />
</ThemeContext.Provider> how to use the value of ThemeContext if you want to use it in the Father file.
can"t get the ThemeContext of the parent component in Father, so how to use Context.Consumer
<ThemeContext.Consumer>
{value => /* render something based on the context value */}
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