(attr)
return attr, (value if delim else None)
splitvalue('attr=value') --> 'attr', 'value'.
splitvalue('attr=value') --> 'attr', 'value'.
splitvalue ( attr = value ) -- > attr value .
def _splitvalue(attr):
    """splitvalue('attr=value') --> 'attr', 'value'."""
    attr, delim, value = attr.partition('=')
    return attr, (value if delim else None)
def _splitvalue ( attr ) : attr , delim , value = attr . partition ( '=' ) return attr , ( value if delim else None )