title: Replace a part of a Python list element
body: <p>I have a csv file like below:</p>
  
  <p>CSV:</p>
  
  <pre><code>H1,H2,H3
  A_B,C1,D
  F_2j,G,p5
  </code></pre>
  
  <p>I'm trying to remove '_' and numbers from the first column. Here's what I've tried</p>
  
  <pre><code>for i in range(len(max(cols, key=len))):
          transposed = ([(c[i] if i&lt;len(c) else '') for c in cols])
          str(transposed[0]).replace("_",";").split()
  </code></pre>
  
  <p>It did replace '_', but the original transposed still prints the same csv file. How can I replace this new column with the old? Also, how can I remove digits just from column1 to give the following output?</p>
  
  <p>Desired output:</p>
  
  <pre><code>H1,H2,H3
  A;B,C1,D
  F;j,G,p5
  </code></pre>