NewTCPPool throws error

[kavemun]

p, err := pool.NewTCPPool(options) //for tcp example using NewTCPPool causes error :- 2020/07/08 10:43:01 &net.OpError{Op:"dial", Net:"tcp", Source:net.Addr(nil), Addr:(*net.TCPAddr)(0xc0002026c0), Err:(*os.SyscallError)(0xc000208180)}