def get_join_parameters(join_kwargs):
    """
    Convenience function to determine the columns to join the right and
    left DataFrames on, as well as any suffixes for the columns.
    """

    by = join_kwargs.get("by", None)
    suffixes = join_kwargs.get("suffixes", ("_x", "_y"))
    if isinstance(by, tuple):
        left_on, right_on = by
    elif isinstance(by, list):
        by = [x if isinstance(x, tuple) else (x, x) for x in by]
        left_on, right_on = (list(x) for x in zip(*by))
    else:
        left_on, right_on = by, by
    return left_on, right_on, suffixes