def __check_duplicate_args(lf_graph: dict) -> bool:
    """ Check for duplicated predicate arguments in logical form graph.

    Parameters:
    lf_graph: dict of id (int) and graph (LogicalFormGraph)

    Returns:
    true if logical form graph has no predicate w/ duplicate arguments

    """
    graph = lf_graph['graph'].graph
    predicate_nodes = [g for g in graph.nodes()
                       if '@' in graph.nodes[g]['predicate']]
    for node in predicate_nodes:
        child_predicates = [graph.nodes[child]['predicate']
                            for child in graph.successors(node)
                            if '@' not in graph.nodes[child]['predicate']]
        if len(child_predicates) > 1 and \
           all(x == child_predicates[0] for x in child_predicates):
            return False
    return True