title: How do I detect missing fields in a CSV file in a Pythonic way?
body: <p>I'm trying to parse a CSV file using Python's <code>csv</code> module (specifically, the <code>DictReader</code> class).  Is there a Pythonic way to detect empty or missing fields and throw an error?</p>
  
  <p>Here's a sample file using the following headers: NAME, LABEL, VALUE</p>
  
  <pre><code>foo,bar,baz
  yes,no
  x,y,z
  </code></pre>
  
  <p>When parsing, I'd like the second line to throw an error since it's missing the VALUE field.</p>
  
  <p>Here's a code snippet which shows how I'm approaching this (disregard the hard-coded strings...they're only present for brevity):</p>
  
  <pre><code>import csv
  
  HEADERS = ["name", "label", "value" ]
  fileH = open('configFile')
  reader = csv.DictReader(fileH, HEADERS)
  
  for row in reader:
      if row["name"] is None or row["name"] == "":
          # raise Error
      if row["label"] is None or row["label"] == "":
          # raise Error
      ...
  fileH.close()
  </code></pre>
  
  <p>Is there a cleaner way of checking for fields in the CSV file w/out having a bunch of <code>if</code> statements?  If I need to add more fields, I'll also need more conditionals, which I would like to avoid if possible.</p>