title: Python: Binary number conversion with an extra letter
body: <p>I am converting large binary numbers to decimal form in a python project.
  I was using this method to convert binary numbers:</p>
  
  <pre><code>for number in binary_numbers:
     integer = int(number, 2)
     integers.append(integer)
  </code></pre>
  
  <p>This accesses a list of binary_numbers and adds the converted number to another list of integers.</p>
  
  <p>Given this binary number: '1101100111001001110110001100100111011001110010001101100011001001110110011100100111011000110010001101100111001000110110001100100'</p>
  
  <p>I got this:
  144745261873314177475604083946266324068L</p>
  
  <p>The number is correct, but there is an 'L' added to the end.</p>
  
  <p>The next smallest number in my series was:
  '110110011100100111011000110010011101100111001000110110001100100'
  which gave me a decimal value of 7846656369001524324 (no 'L')</p>
  
  <p>Why is the 'L' there? Where did it come from? Any help would be much appreciated.</p>