title: How to flip bits using XOR (^) operator?
body: <p>In the editor is the 8 bit variable <code>a</code>. Use a bitmask and the value <code>a</code> in order to achieve a result where all of the bits in <code>a</code> are flipped. Be sure to print your answer as a <code>bin()</code> string!
  Im using PYTHON 2.7
  Please help me to use XOR (<code>^</code>) operator to do this
  <code>a = 0b1000</code></p>