title: Pandas Python, Merge dictionaries
body: <pre><code>A = ["word1" : 4 , "word2" : 1]
  
  df = pandas.DataFrame(data=A)
  </code></pre>
  
  <p>Now some new dictionary comes along, Note: that this dictionary doesn't have "word2".</p>
  
  <pre><code>B = ["word1" : 4 , "word3" : 1, "word4" : 10]
  </code></pre>
  
  <p>How do I merge B and df such that i get the following results:</p>
  
  <pre><code>   word1, word2, word3, word4
  0     4     1       0     0
  1     4     0       1     10
  </code></pre>
  
  <p>Note:  Row 0 = A and Row 1 = B </p>