title: Why can't List contain multiple types?
body: <p>You can mix types inside tuples or lists. Why can't you specify that in typing hints?</p>
  
  <pre><code>&gt;&gt;&gt; from typing import Tuple, List
  &gt;&gt;&gt; t = ('a', 1)
  &gt;&gt;&gt; l = ['a', 1]
  
  &gt;&gt;&gt; t2: Tuple[str, int] = ('a', 1)
  &gt;&gt;&gt; l2: List[str, int] = ['a', 1]
  
  TypeError: Too many parameters for typing.List; actual 2, expected 1
  </code></pre>