def _read(self):
        if not self._buffer:
            self.flush()

        return self._buffer.pop(0)
@return: the absolute position of wrapper on the page
dataset/ETHPy150Open geky/pyDAPLink/pyDAPLink/client/transport.py/DAPLinkClientTransport._read--crossover with--dataset/ETHPy150Open rwl/muntjac/muntjac/ui/drag_and_drop_wrapper.py/WrapperTargetDetails.getAbsoluteLeft