def concatixnames(ixname='ix', source_suffix='source', target_suffix='target'):
    """

    Args:
        ixname (str): 'ix'
        source_suffix (str): 'left'
        target_suffix (str): 'right'

    Returns:
        str, str, list(): 'ix_source', 'ix_target', ['ix_source', 'ix_target']
    """
    ixnamesource = '_'.join([ixname, source_suffix])
    ixnametarget = '_'.join([ixname, target_suffix])
    ixnamepairs = [ixnamesource, ixnametarget]
    return ixnamesource, ixnametarget, ixnamepairs