Create an unabiguous label string

    If facetting over a single variable, `label_value` is
    used, if two or more variables then `label_both` is used.

    Parameters
    ----------
    label_info : series
        Series whose values will be returned. It must have
        an index made of variable names
    multi_line : bool
        Whether to place each variable on a separate line
    sep :  str
        Separation between variable name and value

    Returns
    -------
    out : str
        Contatenated label values (or pairs of variable names
        & values)

def label_context(label_info, multi_line=True, sep=': '):
    """
    Create an unabiguous label string

    If facetting over a single variable, `label_value` is
    used, if two or more variables then `label_both` is used.

    Parameters
    ----------
    label_info : series
        Series whose values will be returned. It must have
        an index made of variable names
    multi_line : bool
        Whether to place each variable on a separate line
    sep :  str
        Separation between variable name and value

    Returns
    -------
    out : str
        Contatenated label values (or pairs of variable names
        & values)
    """
    if len(label_info) == 1:
        return label_value(label_info, multi_line)
    else:
        return label_both(label_info, multi_line, sep)