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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 get_containers(config,
                   all=True,
                   trunc=False,
                   since=None,
                   before=None,
                   limit=-1,
                   *args,
                   **kwargs):
    '''
    Get a list of mappings representing all containers

    all
        Return all containers

    trunc
        Set it to True to have the short ID

    Returns a mapping of containers
    '''
    err = "Unknown"
    client = _get_client(config)
    try:
        ret = client.containers(all=all,
                                trunc=trunc,
                                since=since,
                                before=before,
                                limit=limit)
        return ret
    except Exception as e:
        err = e
    utils.error("Unable to list Docker containers: %s"%err)
    return None