Help/BUG?/issue in documentation? with geompy.getAngle function

I am trying to get the angle of two straight lines, my issue is that I am getting different results between the python function geompy.getAngle(line1,line2) and the GUI/inspection/dimensions/angle and selecting line1 and then line 2.
here it is possible to see the resulting value given by the python function is 80.379 and the interface tool gives 99.62

I have found that the only way to obtain the same result as in GUI interface, was by creating vectors with the same direction as the edges, and the use the function geompy.GetAngleVectors(vector0,vector1) nevertheless this is not the expected behavior that one understand from the documentation and specially that in the GUI I am selecting the edges as it can be seen in the screenshot. (and that I still don’t fully understand the difference of the result (the resulting angles with getAngle are the complementary or suplementary of the ones getting from GetAngleVector)