title: Python 3.6 variable annotations and numeric literals
body: <p>In the documentation on Python in the section "What's new in Python 3.6" among other things there are presented variable annotations and using underscores in numeric literals.</p>
  
  <p>However I tried shown examples and not all of them were passed.</p>
  
  <p>Are these examples incomplete and do they require some additional code that is assumed under the hood?</p>
  
  <p>For example this statement</p>
  
  <pre><code>primes: List[int] = []
  </code></pre>
  
  <p>issues</p>
  
  <pre><code>NameError: name 'List' is not defined
  </code></pre>
  
  <p>This statement</p>
  
  <pre><code>print( 1_000_000_000_000_000 ) 
  </code></pre>
  
  <p>is also considered as wrong.</p>