title: Need type annotation for variable in python 3.5 code
body: <p>I am using <code>mypy</code> on my python 3.5 code, and I got a lot of messages which look like this:</p>
  
  <blockquote>
    <p>file:line number: error: Need type annotation for variable</p>
  </blockquote>
  
  <p>But I read about the new features in <code>python 3.6</code> that it introduced the syntax for variable annotations only in <code>python 3.6</code>:</p>
  
  <blockquote>
    <p>PEP 484 introduced the standard for type annotations of function parameters, a.k.a. type hints. This PEP adds syntax to Python for annotating the types of variables including class variables and instance variables...</p>
  </blockquote>
  
  <p>And if I am trying to add variable type annotations to my variables in the <code>python 3.5</code> program, It throws <code>SyntaxError</code>.</p>
  
  <p>What should I do? Ignore this messages? Update to <code>python 3.6</code>? Why the <code>mypy</code> compiles my code like it's written in <code>python 3.6</code>?</p>