What is the electrical symbol of the socket? How to draw?

L is the live wire of power supply, and the red, yellow, green and live wires can be divided into L 1, L2 and L3. Generally, three-phase four-wire sockets are connected without phase sequence. The three-phase socket is semi-circular, the arc is longer than the diameter, and the bottom is closely connected with T. The single-phase socket is semicircular, and the bottom T is connected together. Waterproof sockets are painted the same as drawings except that they are semi-circular and semi-white, usually black.