title: Use int to convert decimal to bianary
body: <p>I want to convert number 168 to binary using <code>int</code>,<br>
  It report error</p>
  
  <pre><code>In [11]: int(168, base=2)                                                                                                                             
  
  ----&gt; 1 int(168, base=2)
  
  TypeError: int() can't convert non-string with explicit base
  </code></pre>
  
  <p>I read the doc and tried alternativly</p>
  
  <pre><code>In [13]: int("168", base=2)                                                                                                                           
  ValueError: invalid literal for int() with base 2: '168'
  </code></pre>
  
  <p>I learned that <code>bin</code> could get the job done</p>
  
  <pre><code>In [16]: bin(168)                                                                                                                                     
  Out[16]: '0b10101000'
  </code></pre>
  
  <p>How could I use <code>int</code> to do it?</p>