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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 apply_zoom_factor(self):

 """Apply zoom factor"""

        if hasattr(self, 'setZoomFactor'):
            # Assuming Qt >=v4.5
            self.setZoomFactor(self.zoom_factor)
        else:
            # Qt v4.4
            self.setTextSizeMultiplier(self.zoom_factor)