Print benchmark numbers.

def print_benchmark(elapsed):
    """
    Print benchmark numbers.
    """
    print '%-7.2f %s' % (elapsed, 'seconds elapsed')
    keys = ['directories', 'files',
            'logical lines', 'physical lines']
    for key in keys:
        if key in options.counters:
            print '%-7d %s per second (%d total)' % (
                options.counters[key] / elapsed, key,
                options.counters[key])