Reordered the paragraphs describing 'Common Evidence' and 'Common Cause' examples to match the figure (below Image('../images/2/three_nodes.png')) for the same example.
Reordered the paragraphs describing 'Common Evidence' and 'Common Cause' examples to match the figure (below Image('../images/2/three_nodes.png')) for the same example.

pgmpy/pgmpy_notebook