Rotating an Empty at a constant speed, through a Python script I want to make a Python script that rotates an Empty at a certain constant speed.  The python script will rotate this empty for a certain amount of time, and then it will stop. Does anybody know how such a Python script can be made?

The idea of a certain speed, is that I want the empty to rotate along its local axis, a.k.a its own origin, and completing two pi radians in a certain amount of time, so it will rotate a full revolution in time (t), and I want this time to be a variable,  so I can adjust how fast the rotation is. 

My idea is that I wanted to parent a propeller or any other object to this empty,  and when the empty rotates,  the propeller will rotate as well.
Consider just keyframing the rotation of the empty. Simple animation. 0 degrees, 180 degrees, 360 degrees. 3 keyframes and then adjust.  In the graph editor add a cyclic modifier.