title: How to create a lookup table with noise in Python?
body: <p>Say I have a dictionary in Python <code>{1:'a', 100:'b', 1024:'c'}</code></p>
  
  <p>I want to build a function that can look for not only the exact value of the key, but also approximated values. For instance, the function can return <code>b</code> if the input is 99 or 101.</p>
  
  <p>Could you suggest me some approaches?</p>