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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def get_window_size(self, window):
 """ Get a window's size. """

        w_ret = ctypes.c_uint(0)
        h_ret = ctypes.c_uint(0)
        _libxdo.xdo_get_window_size(self._xdo, window, ctypes.byref(w_ret),
                                    ctypes.byref(h_ret))
        return window_size(w_ret.value, h_ret.value)