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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 install_backport_hook(api):
 """ Install a backport import hook for Qt4 api Parameters api : str The Qt4 api whose structure should be intercepted ('pyqt4' or 'pyside'). Example ------- Loaded module AnyQt._backport as a substitute for PyQt4 """

    if api == USED_API:
        raise ValueError

    sys.meta_path.insert(0, ImportHookBackport(api))