Group lhs and rhs into conditional, stable and undefined
    :param node: ast node 
    
    :returns: tuple of (conditional_lhs, stable_lhs),(conditional_rhs, stable_rhs), undefined

def conditional_symbols(node):
    '''
    Group lhs and rhs into conditional, stable and undefined
    :param node: ast node 
    
    :returns: tuple of (conditional_lhs, stable_lhs),(conditional_rhs, stable_rhs), undefined
    
    '''

    gen = ConditionalSymbolVisitor()
    gen.visit(node)
    lhs = gen.cond_lhs, gen.stable_lhs
    rhs = gen.cond_rhs, gen.stable_rhs
    undefined = gen.undefined
    return lhs, rhs, undefined