title: Python tuple access issue?
body: <p>I am using python pyparsing libary whose output seems to be tuple. However, when trying to access as tuple I get unexpected result.</p>
  
  <pre><code>&gt;&gt;&gt; from pyparsing import *
  &gt;&gt;&gt; aaa = (Literal('xxx') + SkipTo(':')  + Literal(':')('::') + Word(nums)('eee')).parseString('xxx : 123')
  
  &gt;&gt;&gt; aaa
  (['xxx', '', ':', '123'], {'eee': [('123', 3)], '::': [(':', 2)]})
  </code></pre>
  
  <p>Here is what is strange:</p>
  
  <pre><code>&gt;&gt;&gt; aaa[0]
  'xxx'
  &gt;&gt;&gt; aaa[1]
  ''
  </code></pre>
  
  <p>I would expect <code>aaa[0]</code> to be the list:</p>
  
  <pre><code>['xxx', '', ':', '123']
  </code></pre>
  
  <p>and aaa[1] - the dictionary:</p>
  
  <pre><code>{'eee': [('123', 3)], '::': [(':', 2)]}
  </code></pre>
  
  <p>Why am I getting the unexpected? What is happening here? Thanks.</p>