title: mypy error: List or tuple literal expected as the second argument to namedtuple()
body: <p>I wrote this code in Python 3.5:</p>
  <pre class="lang-py prettyprint-override"><code>from collections import namedtuple
  
  attributes = ('content', 'status')
  Response = namedtuple('Response', attributes)
  </code></pre>
  <p>When I run the Mypy type checker to analyze this code it raised the error:</p>
  <blockquote>
  <p>error: List or tuple literal expected as the second argument to <code>namedtuple()</code></p>
  </blockquote>
  <p>I tried to add a type annotation to the <code>attributes</code> variable:</p>
  <pre class="lang-py prettyprint-override"><code>from typing import Tuple
  attributes = ('content', 'status')  # type: Tuple[str, str]
  </code></pre>
  <p>But it didn't fix the raised error.</p>