title: Shorthand for defining PyParsing field names
body: <p>I have a few pyparsing tokens defined as follows:</p>
  
  <pre><code>field = Word(alphas + "_").setName("field")
  </code></pre>
  
  <p>Is there really no shorthand for this?</p>
  
  <p>Furthermore, this does not seem to work, the dictionary returned by <code>expression.parseString()</code>  is always an empty one.</p>