def ensureEndPoints(self):
        if (self.m_startPoint is None)  or  (self.m_endPoint is None):
            fillRangePoints(self)
            self.setupLastEndpoints()
Ensure the end points exists and are consisent with the javascript range
dataset/ETHPy150Open pyjs/pyjs/pyjswidgets/pyjamas/selection/Range.py/Range.ensureEndPoints