def list_records_params(req):
    """
    Extract the appropriate request parameters for a ListRecords request

    :param req: flask request object
    :return: a dictionary of parameters
    """
    from_date = req.values.get("from")
    until_date = req.values.get("until")
    oai_set = req.values.get("set")
    resumption_token = req.values.get("resumptionToken")
    metadata_prefix = req.values.get("metadataPrefix")
    return {
        "from_date" : from_date,
        "until_date" : until_date,
        "oai_set" : oai_set,
        "resumption_token" : resumption_token,
        "metadata_prefix" : metadata_prefix
    }