code: func forwardedTLSInfoFromContext(ctx context.Context) (remoteAddr string, cn string, org string, ous []string) {
  	md, _ := metadata.FromIncomingContext(ctx)
  	if len(md[remoteAddrKey]) != 0 {
  		remoteAddr = md[remoteAddrKey][0]
  	}
  	if len(md[certCNKey]) != 0 {
  		cn = md[certCNKey][0]
  	}
  	if len(md[certOrgKey]) != 0 {
  		org = md[certOrgKey][0]
  	}
  	ous = md[certOUKey]
  	return
  }
docs: // forwardedTLSInfoFromContext obtains forwarded TLS CN/OU from the grpc.MD
  // object in ctx.