def field_to_list(row, key):
    """
    Transforms key in row to a list. We split on semicolons if they exist in
    the string, otherwise we use commas.

    Args:
        row: row of data
        key: key for the field we want
    Reutrns:
        row: modified row
    """
    if not row[key]:
        return row
    if ";" in row[key]:
        row[key] = [c.strip() for c in row[key].split(";")]
    elif "," in row[key]:
        row[key] = [c.strip() for c in row[key].split(",")]
    else:
        row[key] = [row[key]]
    return row