Concatenates two or more lists and put result into dest field
    :param input:
    :param params:
    :return:

def list_concat(input, **params):
    """
    Concatenates two or more lists and put result into dest field
    :param input:
    :param params:
    :return:
    """
    PARAM_SOURCE_FIELDS = 'src.fields'
    PARAM_DEST_FIELD = 'dest.field'

    field_list = params.get(PARAM_SOURCE_FIELDS)
    for row in input:
        res = []
        for field in field_list:
            res += row[field]
        row[params.get(PARAM_DEST_FIELD)] = res
    return input