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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 list_extensions(request):
 """List neutron extensions. :param request: django request object """

    neutron_api = neutronclient(request)
    try:
        extensions_list = neutron_api.list_extensions()
    except exceptions.ServiceCatalogException:
        return {}
    if 'extensions' in extensions_list:
        return tuple(extensions_list['extensions'])
    else:
        return ()