Use a turtle to draw a 3-4-5 triangle. Refer to the illustration below:
Here's how to use the python function for arctan:
To get the arctan of 4/3 in radians:
>>> import math
>>> math.atan2(4,3)
To convert radians to degrees, use math.degrees(), like this:
>>> import math
>>> math.degrees(3.14)
Note: In the example above, 3.14 is close to 
, so the answer should be close to 180. You should get different answers for the arctangents of 3/4 and 4/3.