def reverse_column(column: str) ->str:
    """Change column 'xxx_1' to 'xxx_2' and vice versa.

    Examples
    --------
    >>> reverse_column('hello')
    'hello'
    >>> reverse_column('good_bye_1')
    'good_bye_2'
    >>> reverse_column('world_2')
    'world_1'
    """
    for suffix, other in [('_1', '_2'), ('_2', '_1')]:
        if column.endswith(suffix):
            return column[:-len(suffix)] + other
    return column
