How to use the postman-collection.VariableScope.isVariableScope function in postman-collection

init: function (done) {
        var state = this.state;

        // ensure that the environment, globals and collectionVariables are in VariableScope instance format
        state.environment = VariableScope.isVariableScope(state.environment) ? state.environment :
            new VariableScope(state.environment);
        state.globals = VariableScope.isVariableScope(state.globals) ? state.globals :
            new VariableScope(state.globals);
        state.collectionVariables = VariableScope.isVariableScope(state.collectionVariables) ?
            state.collectionVariables : new VariableScope(state.collectionVariables);
        state._variables = new VariableScope();

        // ensure that the items and iteration data set is in place
        !_.isArray(state.items) && (state.items = []);
        !_.isArray(state.data) && (state.data = []);
        !_.isObject(state.data[0]) && (state.data[0] = {});

        // if the location in state is already normalised then go ahead and queue iteration, else normalise the
        // location
        state.cursor = Cursor.box(state.cursor, { // we pass bounds to ensure there is no stale state
            cycles: state.data.length,

init: function (done) {
        var state = this.state;

        // ensure that the environment, globals and collectionVariables are in VariableScope instance format
        state.environment = VariableScope.isVariableScope(state.environment) ? state.environment :
            new VariableScope(state.environment);
        state.globals = VariableScope.isVariableScope(state.globals) ? state.globals :
            new VariableScope(state.globals);
        state.collectionVariables = VariableScope.isVariableScope(state.collectionVariables) ?
            state.collectionVariables : new VariableScope(state.collectionVariables);
        state._variables = new VariableScope();

        // ensure that the items and iteration data set is in place
        !_.isArray(state.items) && (state.items = []);
        !_.isArray(state.data) && (state.data = []);
        !_.isObject(state.data[0]) && (state.data[0] = {});

        // if the location in state is already normalised then go ahead and queue iteration, else normalise the
        // location
        state.cursor = Cursor.box(state.cursor, { // we pass bounds to ensure there is no stale state
            cycles: state.data.length,
            length: state.items.length
        });
        this.waterfall = state.cursor; // copy the location object to instance for quick access

init: function (done) {
        var state = this.state;

        // ensure that the environment, globals and collectionVariables are in VariableScope instance format
        state.environment = VariableScope.isVariableScope(state.environment) ? state.environment :
            new VariableScope(state.environment);
        state.globals = VariableScope.isVariableScope(state.globals) ? state.globals :
            new VariableScope(state.globals);
        state.collectionVariables = VariableScope.isVariableScope(state.collectionVariables) ?
            state.collectionVariables : new VariableScope(state.collectionVariables);
        state._variables = new VariableScope();

        // ensure that the items and iteration data set is in place
        !_.isArray(state.items) && (state.items = []);
        !_.isArray(state.data) && (state.data = []);
        !_.isObject(state.data[0]) && (state.data[0] = {});

        // if the location in state is already normalised then go ahead and queue iteration, else normalise the
        // location
        state.cursor = Cursor.box(state.cursor, { // we pass bounds to ensure there is no stale state
            cycles: state.data.length,
            length: state.items.length
        });

var done = function (err, scope) {
            if (err) { return callback(err); }

            if (!_.isObject(scope)) {
                return done(new Error(LOAD_ERROR_MESSAGE + type));
            }

            callback(null, new VariableScope(VariableScope.isVariableScope(scope) ? scope.toJSON() : scope));
        };