title: name a column and then call items with name instead of index
body: <p>I have a list of columns that I will be analyzing.  Instead of referring back to the specific index such as data[1][2], I'd like to assign a name to a column and then loop through the rows of the columns for different tasks.  How do I assign a name to a column and then is this the correct format to refer back to it?</p>
  
  <pre><code>for x in range (len(data)):  
      if [column_name][x] .... 
  </code></pre>