Write a set of client and server programs in python that will allow users to post or view messages that will appear on a Message Board to simulate an physical message board that is normally put up on various establishments such as schools and universities. Below are some conditions that the system (client/server) needs to fulfil:

• The client and server make use of TCP transport layer protocol.
• When the server is run, it waits for a client to connect.
• A user (connected using the client application) who wants to post a message needs to supply a set of username and password to the server before it is allowed to post any message on the message board.
• Users who only wants to view the message board need not any username or password.
• The content of the message board is sent to the requesting client in clear text.