'Generate a message that briefly describes the actions taken by this
task, in English.'

def get_summary_message(self):

    parts = []
    for (k, v) in self.counters.iteritems():
        if (v == 0):
            continue
        if (v == 1):
            plural = ''
        else:
            plural = 's'
        parts.append(('%s    %d    container%s' % (k, v, plural)))
    if parts:
        return (',    '.join(parts) + '.')
    else:
        return 'No    action    taken.'
