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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 accel_decrease_transparency(self, *args):
 """Callback to decrease transparency. """

        transparency = self.settings.styleBackground.get_int('transparency')
        if int(transparency) + 2 < MAX_TRANSPARENCY:
            self.settings.styleBackground.set_int('transparency', int(transparency) + 2)
        return True