title: node-fetch error while loading trained model in tensorflow.js
body: <p>After training my tensorflow model, I converted it to the json format as required by tensorflow.js. However when I tried to load this model using javascript, I get a <code>node-fetch</code> error.</p>
  <p>This is my code :</p>
  <pre><code>const tf = require(&quot;./tf.min.js&quot;);
  (async function () {
    const modelURL = &quot;model_js/model.json&quot;;
    const model = await tf.loadLayersModel(modelURL);
    model.summary();
  })();
  </code></pre>
  <p>Complete error logs :</p>
  <pre><code>(node:35092) UnhandledPromiseRejectionWarning: Error: Cannot find module 'node-fetch'
      at Function.Module._resolveFilename (internal/modules/cjs/loader.js:582:15)
      at Function.Module._load (internal/modules/cjs/loader.js:508:25)
      at Module.require (internal/modules/cjs/loader.js:637:17)
      at require (internal/modules/cjs/helpers.js:22:18)
      at pw (/Users/suraj/Desktop/fake-news/tf.min.js:17:225676)
      at t.e.fetch (/Users/suraj/Desktop/fake-news/tf.min.js:17:225911)
      at t.&lt;anonymous&gt; (/Users/suraj/Desktop/fake-news/tf.min.js:17:255546)
      at u (/Users/suraj/Desktop/fake-news/tf.min.js:17:104674)
      at Generator._invoke (/Users/suraj/Desktop/fake-news/tf.min.js:17:104427)
      at Generator.forEach.t.(anonymous function) [as next] (/Users/suraj/Desktop/fake-news/tf.min.js:17:105031)
  (node:35092) UnhandledPromiseRejectionWarning: Unhandled promise rejection. This error originated either by throwing inside of an async function without a catch block, or by rejecting a promise which was not handled with .catch(). (rejection id: 3)
  (node:35092) [DEP0018] DeprecationWarning: Unhandled promise rejections are deprecated. In the future, promise rejections that are not handled will terminate the Node.js process with a non-zero exit code.
  </code></pre>