title: Convert a pandas "Series of pair arrays" to a "two-column DataFrame"?
body: <p>I have a Pandas Series that consists of arrays of pairs:</p>
  
  <pre><code>In [177]: pair_arrays
  Out[177]: 
  15192     [[1, 9], [2, 14], [4, 1], [5, 36], [6, 8], [7,...
  16012     [[0, 107], [1, 42], [2, 22], [3, 59], [4, 117]...
  17523     [[0, 44], [1, 36], [2, 43], [3, 28], [4, 52], ...
  ...
  </code></pre>
  
  <p>I would like to reshape that into a dataframe with two columns, 'x' and 'y', which has a shape similar to:</p>
  
  <pre><code>In [179]: pd.DataFrame([{'x':1, 'y':42}, {'x':4, 'y':12}], columns=['x', 'y'])
  Out[179]: 
     x   y
  0  1  42
  1  4  12
  ...
  </code></pre>
  
  <p>How do I do this?</p>