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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 containers_running(get_container_name):
 """ Return a list of containers tracked by this environment that are running """

    running = []
    for n in ['web', 'postgres', 'solr', 'datapusher', 'redis']:
        info = docker.inspect_container(get_container_name(n))
        if info and not info['State']['Running']:
            running.append(n + '(halted)')
        elif info:
            running.append(n)
    return running