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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 upgradestep(upgrade_product, version):
 """ Decorator for updating the QuickInstaller of a upgrade """

    def wrap_func(fn):
        def wrap_func_args(context, *args):
            p = getToolByName(context, 'portal_quickinstaller').get(upgrade_product)
            setattr(p, 'installedversion', version)
            return fn(context, *args)
        return wrap_func_args
    return wrap_func