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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 _render(self):
 """ redraws render window if the render window exists """

        if hasattr(self, 'ren_win'):
            if hasattr(self, 'render_trigger'):
                self.render_trigger.emit()
            elif not self._first_time:
                self.render()