title: How to implement negative infinity in python?
body: <p>I am trying to implement a Heap defined Priority Queue, the algorithm is from CLRS book chapter 6.
  The pseudocode is listed below:</p>
  
  <pre><code>Max_Heap_Insert(A, key):
      A.heap_size = A.heap_size + 1
      A[A.heap_size] = -∞
      Heap_Increase_Key(A, A.heap_size, key)
  </code></pre>
  
  <p>My question is that using python, how do I define -∞?</p>