// Package singleflight provides a duplicate function call suppression
// mechanism. This package is a fork of the Go golang.org/x/sync/singleflight
// package. The package is forked, because the package a part of the unstable
// and unversioned golang.org/x/sync module.
//
// https://github.com/golang/sync/tree/67f06af15bc961c363a7260195bcd53487529a21/singleflight
package singleflight