class TransportUtils:

    def __init__(self, host, port, login, password):
        self.host = host
        self.port = port
        self.login = login
        self.password = password

    def open_connection(self):
        self.client = paramiko.SSHClient()

        self.client.set_missing_host_key_policy(paramiko.AutoAddPolicy())

        self.client.connect(hostname=self.host, port=self.port, username=self.login, password=self.password)


    def get_transport(self):
        if self.client is None:
            open_connection(self)

        stdin, stdout, stderr = self.client.exec_command('ls -a')  # ('apt list --installed')

        results = stdout.read()

        transport: paramiko.Transport = self.client.get_transport()

        if transport is None:
            raise UnknownTransport()

        return transport