def __setitem__(self, name, value):
if not _is_string_like(value): value=str(value)
ghandle=gv.agroot(self.handle) # get root graph
if ghandle==self.handle:
gv.agattr_label(self.handle,self.type,name,value)
else:
gv.agsafeset_label(ghandle,self.handle,name,value,'')
def subgraph_root(self, nbunch=None, name=None):
"""Return root graph of subgraph or None if graph is root graph.
"""
handle=gv.agroot(self.handle)
if handle is None: return None
H=self.__class__(strict=self.strict,
directed=self.directed,
handle=handle,name=name)
return H