Hi,

I updated graph-tool to 2.9 and I got an exception from find_vertex_range method (see below). Can you confirm this is a bug?

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In [1]: import graph_tool.all as gt
In [2]: g = gt.Graph()
In [3]: g.add_edge_list([(0,1),(0,2),(1,2)])
In [4]: g.degree_property_map("out").a
Out[4]: PropertyArray([2, 1, 0], dtype=int32)
In [5]: gt.find_vertex_range(g,g.degree_property_map("out"),(2,3))
---------------------------------------------------------------------------
NameError                                 Traceback (most recent call last)
<ipython-input-5-e6f941427c2a> in <module>()
----> 1 gt.find_vertex_range(g,g.degree_property_map("out"),(2,3))

/usr/lib/python2.7/dist-packages/graph_tool/util/__init__.pyc in find_vertex_range(g, prop, range)
     65     ret = libgraph_tool_util.\
     66           find_vertex_range(g._Graph__graph, _degree(g, prop),
---> 67                             (_convert(prop, range[0]), _convert(prop, range[1])))
     68     return ret
     69

NameError: global name '_convert' is not defined

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Regards,

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