TypeError: Network request failed
    at XMLHttpRequest.xhr.onerror ......

yarn add isomorphic-fetch

import fetch from "isomorphic-fetch";

Index: manuscript/chapter3.md
IDEA additional info:
Subsystem: com.intellij.openapi.diff.impl.patch.CharsetEP
<+>UTF-8
===================================================================
--- manuscript/chapter3.md	(date 1553926587000)
+++ manuscript/chapter3.md	(date 1554154244000)
@@ -1218,8 +1218,8 @@
 
 ### Exercises:
 
-* Confirm your [source code for the last section](http://bit.ly/2HoLAGY)
-  * Confirm the [changes from the last section](http://bit.ly/2HquJnd)
+* Confirm your [source code for the last section](http://bit.ly/2Ukfao7)
+  * Confirm the [changes from the last section](http://bit.ly/2HS0gzu)
 * Read about [React's Error Handling for Components](https://reactjs.org/blog/2017/07/26/error-handling-in-react-16.html)
 
 ## Axios instead of Fetch

const Search = ({ value, onChange, children }) => (
  <form>
    <label>
      {children}
        <input type="text" value={value} onChange={onChange} />
    </label>
  </form>
);

(node:36647) UnhandledPromiseRejectionWarning: Unhandled promise rejection (rejection id: 2): TypeError: "listener" argument must be a function
(node:36647) 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.

v7.7.2

4.1.2

[email protected]

macOS Sierra version 10.12.5