graphs.lovasz_theta breaks on the Tutte graph

[math1um]

g=graphs.TutteGraph()

g.lovasz_theta() reports an error (why?!):

Error in lines 1-1 Traceback (most recent call last): File "/cocalc/lib/python3.8/site-packages/smc_sagews/sage_server.py", line 1230, in execute exec( File "", line 1, in File "", line 1893, in lovasz_theta File "/ext/sage/sage-9.3/local/lib/python3.9/site-packages/sage/graphs/lovasz_theta.py", line 70, in lovasz_theta g = graph.relabel(inplace=False, perm=range(1, n + 1)).networkx_graph() File "/ext/sage/sage-9.3/local/lib/python3.9/site-packages/sage/graphs/generic_graph.py", line 21517, in relabel perm2 = G.relabel(perm, File "/ext/sage/sage-9.3/local/lib/python3.9/site-packages/sage/graphs/generic_graph.py", line 21573, in relabel perm = dict(zip(self.vertices(), it)) File "/ext/sage/sage-9.3/local/lib/python3.9/site-packages/sage/graphs/generic_graph.py", line 10625, in vertices return sorted(self.vertex_iterator(degree=degree, vertex_property=vertex_property), key=key) TypeError: '<' not supported between instances of 'int' and 'tuple'