parsing times like "5 minutes ago"?

[mh at pixar.com]

I'm looking for something like Tcl's [clock scan] command which parses
human-readable time strings such as:

    % clock scan "5 minutes ago"
    1246925569
    % clock scan "tomorrow 12:00"
    1246993200
    % clock scan "today + 1 fortnight"
    1248135628

Does any such package exist for Python?

Many TIA!
Mark

-- 
Mark Harrison
Pixar Animation Studios