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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 resource_listing(cls, request) -> [(200, 'Ok', ResourceListingModel)]:
        '''Return the list of all available resources on the system.

        Resources are filtered according to the permission system, so querying
        this resource as different users may bare different results.'''
        apis = [api.get_swagger_fragment() for api in Api if not api.private]
        Respond(200, {
            'apiVersion': cls.api.version,
            'swaggerVersion': cls.api.swagger_version,
            'apis': apis
        })