communication ros-gazebo-simulation python

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Hi, im using ros-kinetic-gazebo-py (simulated). I have 3 robots, one hector_uav and 2 turtlebots

my first tb3 have to send a msg to other two, and receive a message telling they are ready do start a mission.

then hector_uav have to go to the point, then he send a message to tb3_lead , that leader have to look for a object, since he found he have to get this location and send to second turtlebot. then i finish my mission.

i would like to know how can i make this communication