Closeness not included in module

Hi there, when I try to calculate the closeness metric it says it's not in
the module. I have tried to import it and in fact I cannot find it, simply
put. I can correctly calculate all the other centralities. Was it added very
recently maybe, and I don't have the latest version?

Thanks in advance

Everything seems fine:

    from graph_tool.all import *
    g = collection.data["power"]
    c = closeness(g)

When having problems, please always provide a short example...

Cheers,
Tiago