title: Check whether a map contains all contents of another map
body: <p>I am trying to check whether a map contains all contents of another map. For example, I have a <code>mapA</code> which is a <code>Map&lt;String, List&lt;String&gt;&gt;</code> and the elements are:</p>
  
  <pre><code>"1" -&gt; ["a","b"]
  "2" -&gt; ["c","d"]
  </code></pre>
  
  <p>another <code>mapB</code> which is also a <code>Map&lt;String, List&lt;String&gt;&gt;</code>, the elements are:</p>
  
  <pre><code>"1" -&gt; ["a"]
  "2" -&gt; ["c","d"],
  </code></pre>
  
  <p>I want to create a function <code>compare(mapA, mapB)</code> which will return false in this case.</p>
  
  <p>What is the best way to do this?</p>