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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 data_only_container(name, volumes):
 """ create "data-only container" if it doesn't already exist. We'd like to avoid these, but postgres + boot2docker make it difficult, see issue #5 """

    info = inspect_container(name)
    if info:
        return
    c = _get_docker().create_container(
        name=name,
        image='datacats/postgres',  # any image will do
        command='true',
        volumes=volumes,
        detach=True)
    return c