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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 wsgi_proxyfix(factory=None):
 """Fix ``REMOTE_ADDR`` based on ``X-Forwarded-For`` headers. .. note:: You must set ``WSGI_PROXIES`` to the correct number of proxies, otherwise you application is susceptible to malicious attacks. .. versionadded:: 1.0.0 """

    def create_wsgi(app, **kwargs):
        wsgi_app = factory(app, **kwargs) if factory else app.wsgi_app
        if app.config.get('WSGI_PROXIES'):
            return ProxyFix(wsgi_app, num_proxies=app.config['WSGI_PROXIES'])
        return wsgi_app
    return create_wsgi