title: Find indices of a value in 2d matrix
body: <p>I have a matrix of the form,</p>
  
  <pre><code>mymatrix=[[1,2,3],[4,5,6],[7,8,9]]
  </code></pre>
  
  <p>I want to the get the index of, say for example, 9 which is at (2,2).</p>
  
  <p>What I have tried to do so far.</p>
  
  <pre><code>for i,j in enumerate(mymatrix):
     for k,l in enumerate(j):
       if l==9:
           print i,k
  </code></pre>
  
  <p>Is there a better way of doing the same. Optimization,  anyone? Thanks in advance.</p>