code: def setup_app(app, api):
      
      api.add_resource(
          KnwKBAllResource,
          '/api/knowledge'
      )
      api.add_resource(
          KnwKBResource,
          '/api/knowledge/<string:slug>'
      )
      api.add_resource(
          KnwKBMappingsResource,
          '/api/knowledge/<string:slug>/mappings'
      )
      api.add_resource(
          KnwKBMappingsToResource,
          '/api/knowledge/<string:slug>/mappings/to'
      )
      api.add_resource(
          KnwKBMappingsFromResource,
          '/api/knowledge/<string:slug>/mappings/from'
      )
  
      # for other urls, return "Method Not Allowed"
      api.add_resource(
          NotImplementedKnowledegeResource,
          '/api/knowledge/<string:slug>/<path:foo>'
      )
docs: setup the resources urls.