title: Pandas: Flatten Nested Dictionary vertically
body: <p>I have a list of dictionary as below:</p>
  <pre><code>[{'name': 'jack', 'tagList': [{'tagId': '10', 'tagName': 'AB'},{'tagId': '20', 
  'tagName': 'BC'}]}, 
   {'name': 'mike', 'tagList': [{'tagId': '30', 'tagName': 'DE'},{'tagId': '40', 
  'tagName': 'FG'}]}]
  </code></pre>
  <p>I want to turn this into a dataframe like below:</p>
  <pre><code>Name   tagList_tagID   tagList_tagName      
  Jack        10               AB
  Jack        20               BC
  mike        30               DE
  mike        40               FG
  </code></pre>
  <p>How can I convert this list of dictionaries to pandas dataframe in an efficient way.</p>