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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def objref(obj):
 """Return a string that uniquely and compactly identifies an object."""

    ref = _objrefs.get(obj)
    if ref is None:
        clsname = obj.__class__.__name__.split('.')[-1]
        seqno = _lastids.setdefault(clsname, 1)
        ref = '{}-{}'.format(clsname, seqno)
        _objrefs[obj] = ref
        _lastids[clsname] += 1
    return ref