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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 select_window(self):
 """ Select window. Return ``self``. To select a window object asynchrously. If a ``window`` object exists and is no longer longer the current window, ``w.select_window()`` will make ``w`` the current window. Returns ------- :class:`Window` """

        target = ('%s:%s' % (self.get('session_id'), self.index),)
        return self.session.select_window(target)