$ gulp less

[15:45:55] Using gulpfile C:\xampp\htdocs\lagou\webApp\gulpfile.js

[15:45:55] Starting 'less'...

[15:45:55] 'less' errored after 8.94 ms

[15:45:55] TypeError: $.less is not a function

    at Gulp.<anonymous> (C:\xampp\htdocs\lagou\webApp\gulpfile.js:28:13)

    at module.exports (C:\xampp\htdocs\lagou\webApp\node_modules\orchestrator\lib\runTask.js:34:7)

    at Gulp.Orchestrator._runTask (C:\xampp\htdocs\lagou\webApp\node_modules\orchestrator\index.js:273:3)

    at Gulp.Orchestrator._runStep (C:\xampp\htdocs\lagou\webApp\node_modules\orchestrator\index.js:214:10)

    at Gulp.Orchestrator.start (C:\xampp\htdocs\lagou\webApp\node_modules\orchestrator\index.js:134:8)

    at C:\Users\Administrator\AppData\Roaming\npm\node_modules\gulp\bin\gulp.js:129:20

    at _combinedTickCallback (internal/process/next_tick.js:73:7)

    at process._tickCallback (internal/process/next_tick.js:104:9)

    at Module.runMain (module.js:606:11)

    at run (bootstrap_node.js:393:7)

var $=require('gulp-load-plugins')();在后面了括号，但是出现$.less is not a function

  "devDependencies": {

    "gulp": "^3.9.1",

    "gulp-clean": "^0.3.2",

    "gulp-concat": "^2.6.1",

    "gulp-connect": "^5.0.0",

    "gulp-cssmin": "^0.2.0",

    "gulp-imagemin": "^3.2.0",

    "gulp-load-plugins": "^1.5.0",

    "gulp-uglify": "^3.0.0",

    "less": "^2.7.2",

    "open": "0.0.5"

  },

package.json 也依赖了，找不出问题，请老师看看