VB.NET Импорт случайных прокси WebRequest

Question

Не могли бы вы помочь мне реализовать случайно меняющуюся систему прокси?Я не знаю, куда положить руки!

Private Function Auth(user As String, password As String) As String
        Dim ret = String.Empty
        Try
            Dim data = "Nothing for now"
            Dim byteArray As Byte() = Encoding.UTF8.GetBytes(data)
            Dim webReq = DirectCast(WebRequest.Create(New Uri("Website")), HttpWebRequest)
            webReq.Method = "POST"
            webReq.ContentType = "application/json"
            webReq.ContentLength = byteArray.Length
            Dim newStream As Stream = webReq.GetRequestStream()
            newStream.Write(byteArray, 0, byteArray.Length)
            newStream.Close()
            Dim response = DirectCast(webReq.GetResponse(), HttpWebResponse)
            Dim sr = New StreamReader(response.GetResponseStream(), Encoding.[Default])
            ret = sr.ReadToEnd()
            sr.Close()
            response.Close()
            newStream.Close()
        Catch ex As Exception
            MessageBox.Show(ex.Message)
        End Try
        Return ret
    End Function