title: Exception during parsing
body: <p>I was trying to built a parser to parse through my dataset but an exception is raised . I am newbie and haven't used parsing much.</p>
  
  <p>I can add arguments to parser but as soon as the function is built an exception is raised.</p>
  
  <p><a href="https://i.stack.imgur.com/7PHJc.png" rel="nofollow noreferrer">The code I am trying is this</a>
  <a href="https://i.stack.imgur.com/lLaUT.png" rel="nofollow noreferrer">The error I am getting is this</a></p>