from igraph import *

g = Graph(directed=True)        # directed edges

g.add_vertices(5)
g.add_edges( [ (0, 0) ] );	# graphObject.add_edges( [ (start_vertex, end_vertex) ] )
g.add_edges( [ (0, 1) ] );
g.add_edges( [ (1, 2) ] );
g.add_edges( [ (2, 3) ] );
g.add_edges( [ (3, 4) ] );
g.add_edges( [ (4, 3) ] );
g.add_edges( [ (3, 5) ] );
g.add_edges( [ (4, 4) ] );
g.add_edges( [ (5, 2) ] );

# g.layout_graphopt() is just one layout algorithm,
# others are available @ http://cneurocvs.rmki.kfki.hu/igraph/doc/python/igraph.GraphBase-class.html
plot(g, layout = g.layout_graphopt() )