title: Replace column in one csv file from other csv file
body: <p>I have one csv file with below data. (, seperated)</p>
  
  <pre><code>C1,C2,C3,C4
  1,2,3,4
  5,6,7,8
  </code></pre>
  
  <p>Now I have other mapping csv file as below</p>
  
  <pre><code>D1,D2
  1,X
  5,Y
  </code></pre>
  
  <p>Here I want to find mapping in second csv file and update its value in first csv file.</p>
  
  <p>Expected Output (If I want to update C3 in first csv file against two records in second mapping file)</p>
  
  <pre><code>C1,C2,C3,C4
  1,2,X,4
  5,6,Y,8
  </code></pre>