def _format_column_name(raw_column_name, year=None):
    """Formats a raw column name to remove: spaces, year and character with
    accents.

    Args:
        raw_column_name (str): a column name
        year: the year tu remove

    Returns:
        (str) The formatted column name.
    """
    raw_column_name = ('_'.join(raw_column_name.lower().split()))
    if year is not None:
        raw_column_name = raw_column_name.replace('_en_{}_'.format(year), '_')
    formatted_column_name = raw_column_name.replace('é', 'e')
    return formatted_column_name