A python's beginner exerxise
<p>I work on "Think Python" and I'm having some trouble with this exercise:</p>

<blockquote>
  <p>Python provides a built-in function called <code>len</code> that returns the length of a string, so the
  value of <code>len('allen')</code> is <code>5</code>.
  Write a function named <code>right_justify</code> that takes a string named <code>s</code> as a parameter and prints the
  string with enough leading spaces so that the last letter of the string is in column 70 of the display.</p>
</blockquote>
