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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 exempt_urls(self):
 """Generate and return a set of url paths to exempt from SessionRefresh This takes the value of ``settings.OIDC_EXEMPT_URLS`` and appends three urls that mozilla-django-oidc uses. These values can be view names or absolute url paths. :returns: list of url paths (for example "/oidc/callback/") """

        exempt_urls = list(self.get_settings('OIDC_EXEMPT_URLS', []))
        exempt_urls.extend([
            'oidc_authentication_init',
            'oidc_authentication_callback',
            'oidc_logout',
        ])

        return set([
            url if url.startswith('/') else reverse(url)
            for url in exempt_urls
        ])