title: Graph networkx from python dict
body: <p>I need help with networkX or any other graph lib in python. 
  I have dictionary with keys and for every key a few value:</p>
  
  <pre><code>{nan: array([nan, nan, nan, nan, nan, nan, nan], dtype=object),
   'BBDD': array([nan, nan, nan, nan, nan, nan, nan], dtype=object),
   'AAAD': array(['BBDD', nan, nan, nan, nan, nan, nan], dtype=object),
   'AAFF': array(['AAAD', nan, nan, nan, nan, nan, nan], dtype=object),
   'MMCC': array(['AAAD', nan, nan, nan, nan, nan, nan], dtype=object),
   'KKLL': array(['AAFF', 'MMCC', 'AAAD', 'BBDD', nan, nan, nan], dtype=object),
   'GGHH': array(['KKLL', 'NI4146', 'MMCC', nan, nan, nan, nan],dtype=object), ...}
  </code></pre>
  
  <p>Now my question is, how can I put data from this dict to graph, where keys would be nodes and values would be edges. Which way is the best for iteration through dict? </p>
  
  <pre><code>import networkx as nx
  import matplotlib.pyplot as plt
  
  g = nx.DiGraph()
  g.add_nodes_from([1,2,3,4,5])
  g.add_edge(1,2)
  g.add_edge(4,2)
  g.add_edge(3,5)
  g.add_edge(2,3)
  g.add_edge(5,4)
  
  nx.draw(g,with_labels=True)
  plt.draw()
  plt.show()
  </code></pre>
  
  <p>It should be something like this, but with other data </p>