>>> from networkx import *
>>> from networkx.io import *
>>> from networkx.operators import *
>>> import os,tempfile

>>> G=Graph(name="test")
>>> e=[('a','b'),('b','c'),('c','d'),('d','e'),('e','f'),('a','f')]
>>> G.add_edges_from(e)
>>> G.add_node('g')
>>> DG=G.to_directed()
>>> XG=XGraph(multiedges=True,selfloops=True)
>>> XG.add_edges_from([(1,2,5),(1,2,5),(1,2),(3,3,42)])


YAML
----

>>> (fd,fname)=tempfile.mkstemp()
>>> write_yaml(G,fname);  
>>> Gin=read_yaml(fname);
>>> sorted(G.nodes())==sorted(Gin.nodes())
True
>>> sorted(G.edges())==sorted(Gin.edges())
True
>>> os.close(fd)
>>> os.unlink(fname)


>>> (fd,fname)=tempfile.mkstemp()
>>> write_yaml(DG,fname);  
>>> Gin=read_yaml(fname);
>>> sorted(DG.nodes())==sorted(Gin.nodes())
True
>>> sorted(DG.edges())==sorted(Gin.edges())
True
>>> os.close(fd)
>>> os.unlink(fname)


>>> (fd,fname)=tempfile.mkstemp()
>>> write_yaml(XG,fname);  
>>> Gin=read_yaml(fname);
>>> sorted(XG.nodes())==sorted(Gin.nodes())
True
>>> sorted(XG.edges())==sorted(Gin.edges())
True
>>> os.close(fd)
>>> os.unlink(fname)