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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_active_window(self):
 """ Get the currently-active window. Requires your window manager to support this. Uses ``_NET_ACTIVE_WINDOW`` from the EWMH spec. """

        window_ret = window_t(0)
        _libxdo.xdo_get_active_window(self._xdo, ctypes.byref(window_ret))
        return window_ret.value