#=========================================================================
aSession.startOperation()
aStartPoint = geomDataAPI_Point2D(aSketchLineA.attribute("StartPoint"))
-aStartPoint.setValue(0., 30.)
+aStartPoint.setValue(0., -30.)
aConstraint.execute()
aSession.finishOperation()
assert (angle(aSketchLineA, aSketchLineB) == ANGLE_DEGREE)