Find all imported interfaces that object supports

I have an object like os.Stdout and I want to know if it supports io.WriteCloser on my platform. I can get the type of my object, but it doesn't tell me anything about interfaces.

package main

import ("fmt"; "reflect"; "os")

func main() {
    fmt.Println(reflect.TypeOf(os.Stdout))
}

This code prints *os.File to console.

I can manually lookup if os.File matches io.WriteCloser methods, but I am curious to know all interfaces that this object supports. Is that possible?