title: Python how to iterate over nested dictionary and change values?
body: <p>I have data that looks as follows</p>
  
  <pre><code>{'exchange1': [{'price': 9656.04, 'side': 'bid', 'size': 0.16, 'timestamp': 1589504786}, 
                 {'price': 9653.97, 'side': 'ask', 'size': 0.021, 'timestamp': 1589504786}], 
  'exchange2': [{'price': 9755.3, 'side': 'bid', 'size': 27.0, 'timestamp': 1589504799},
                {'price': 9728.0, 'side': 'bid', 'size': 1.0, 'timestamp': 1589504799}]}
  </code></pre>
  
  <p>I want to iterate over each exchange and then for all prices and change them depending on the <code>side</code> key.
  If <code>side : bid</code> I want to multiply that <code>price</code> by a number (ex: 0.99) and if  <code>side : ask</code> I want to multiply the price by a different number (ex: 1.01).</p>
  
  <p>I am not sure how to iterate on the list of dictionaries that contain the side and price data.</p>
  
  <p>Thank you for your help.</p>