What does ^= do in python : <p>I have seen the operator ^= in code now once and I dont know what it does. This was used to find a single occurrence of a number in an array. So A = [1,1,2,3,3] it should return 2.  This is how it was used</p>

<pre><code>def solution(A):
    lone_num = 0
    for number in A:
        lone_num ^= number
    return lone_num
</code></pre>

<p>Not particularly sure what it does. </p>
