func (p *Player) Seek(offset time.Duration) error {
	return p.p.Seek(offset)
}
func (p *Player) Seek(offset time.Duration) error {
	return p.p.Seek(offset)
}
// Seek seeks the position with the given offset.
//
// The passed source to NewPlayer must be io.Seeker, or Seek panics.
//
// Seek returns error when seeking the source stream returns error.