completed exercise 3.1

parts/3/phonebookBackend/node_modules/is-promise/readme.md

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+<a href="https://promisesaplus.com/"><img src="https://promisesaplus.com/assets/logo-small.png" align="right" /></a>
+
+# is-promise
+
+  Test whether an object looks like a promises-a+ promise
+
+ [![Build Status](https://img.shields.io/travis/then/is-promise/master.svg)](https://travis-ci.org/then/is-promise)
+ [![Dependency Status](https://img.shields.io/david/then/is-promise.svg)](https://david-dm.org/then/is-promise)
+ [![NPM version](https://img.shields.io/npm/v/is-promise.svg)](https://www.npmjs.org/package/is-promise)
+
+
+
+## Installation
+
+    $ npm install is-promise
+
+You can also use it client side via npm.
+
+## API
+
+```typescript
+import isPromise from 'is-promise';
+
+isPromise(Promise.resolve());//=>true
+isPromise({then:function () {...}});//=>true
+isPromise(null);//=>false
+isPromise({});//=>false
+isPromise({then: true})//=>false
+```
+
+## License
+
+  MIT