title: SyntaxError: non-default argument follows default argument
body: <pre><code>from os import system
  def a(len1,hgt=len1,til,col=0):
      system('mode con cols='+len1,'lines='+hgt)
      system('title',til)
      system('color',col)
  
  a(64,25,"hi","0b")
  input()
  </code></pre>
  
  <p>When I run this, it rejects "def a(..." and highlights "(" in red. I have no clue why.</p>