title: Simple edit to a binary file in python
body: <p><strong>THIS SHOULD BE EASY!</strong>  But i've been unable to find the answer to this question.</p>
  
  <p>Using python, I want to read a binary file into memory, modify the first four bytes of the file, and then write the file back. </p>
  
  <p>There has to be a simple way to edit four measly bytes! right?</p>