code: function newGroovyClosure(groovyClosureString) {
          // The groovy string must be a closure expression, e.g. '{ x -> println(x) }'.
          assert.ok(_isClosure(groovyClosureString));
          return new Tinkerpop.GroovyLambda(groovyClosureString, _groovyScriptEngine);
      }
docs: #### `newGroovyClosure(groovyClosureString: string)` Creates a lambda function from a groovy closure string.