title: How to get enum key by value in Typescript?
body: <p>I have an enum like this:</p>
  
  <pre><code>export enum Colors {
      RED = "RED COLOR",
      BLUE = "BLUE COLOR",
      GREEN = "GREEN COLOR"
  }
  </code></pre>
  
  <p>Could you let me know how to get enum key by value please? i.e., I need to pass "BLUE COLOR" and get 'BLUE'.</p>
  
  <p><code>Colors["BLUE COLOR"]</code> gives error <code>Element implicitly has an 'any' type because expression of type '"BLUE COLOR"' can't be used to index type 'typeof Colors'. Property 'BLUE COLOR' does not exist on type 'typeof Colors'.</code></p>