Bytes/String node name interaction with NX

[nicktimko]

I'm trying to use this bootleg (:P, fix #12 ASAP!) package with NX 1.9.1 and Python 3 on Windows with GV 2.38 and when NX tries to read back in the position data, it coughs because of this line (errors a couple lines down when it tries to get the 0th element of an empty list) because it seems to think the nodes are named with bytes (py2 string), rather than unicode (py3 string). Without the encode it works (on Python 3 at least...can't easily switch to 2 on Windows)...

Aaanyways, I'm not sure if this should be fixed here or in NX. It's probably not been noticed/reported there because the "official" (#12...) pydot only supports Python 2.

Here's a monkeypatch that seems to work wherein I strip out the .encode()

import pydot
import networkx as nx
from networkx.drawing.nx_pydot import to_pydot, make_str
def pydot_layout(G,prog='neato',root=None, **kwds):
    """Create node positions using Pydot and Graphviz.
    Returns a dictionary of positions keyed by node.
    Examples
    --------
    >>> G=nx.complete_graph(4)
    >>> pos=nx.pydot_layout(G)
    >>> pos=nx.pydot_layout(G,prog='dot')
    """
    #pydot = load_pydot() #### EDIT (but not really important for this)

    P=to_pydot(G)
    if root is not None :
        P.set("root",make_str(root))

    D=P.create_dot(prog=prog)

    if D=="":  # no data returned
        print("Graphviz layout with %s failed"%(prog))
        print()
        print("To debug what happened try:")
        print("P=pydot_from_networkx(G)")
        print("P.write_dot(\"file.dot\")")
        print("And then run %s on file.dot"%(prog))
        #return

    Q=pydot.graph_from_dot_data(D)

    node_pos={}
    for n in G.nodes():
        ####################################################
        pydot_node = pydot.Node(make_str(n)).get_name()#.encode('utf-8') # no encode = fix
        ####################################################
        node=Q.get_node(pydot_node)

        if isinstance(node,list):
            node=node[0]
        pos=node.get_pos()[1:-1] # strip leading and trailing double quotes
        if pos != None:
            xx,yy=pos.split(",")
            node_pos[n]=(float(xx),float(yy))
    return node_pos
nx.drawing.nx_pydot.pydot_layout = pydot_layout