title: pandas list of json into columns
body: <p>I have a csv file with a json column. the json column contains an array of json objects. how can I normalize this json data into columns and keep the main id for the record</p>
  
  <p>CSV data:</p>
  
  <pre><code>id  actions
  1   [{"A": 47, "action": "views"}]
  2   [{"K": 70, "action": "conversions"}, {"J": 83, "action": "views"}]
  </code></pre>
  
  <p>expected data frame output should be something like this:</p>
  
  <pre><code>#   A    K    J     action        id
  # 0 47   0    0     views         1
  # 1 0    70   0     conversions   2
  # 2 0    0    83    views         2
  </code></pre>