print the alignment based on a node mapping
    Args:
        mapping: current node mapping list
        instance1: nodes of AMR 1
        instance2: nodes of AMR 2

def print_alignment(mapping, instance1, instance2):
    """
    print the alignment based on a node mapping
    Args:
        mapping: current node mapping list
        instance1: nodes of AMR 1
        instance2: nodes of AMR 2

    """
    result = []
    for instance1_item, m in zip(instance1, mapping):
        r = instance1_item[1] + "(" + instance1_item[2] + ")"
        if m == -1:
            r += "-Null"
        else:
            instance2_item = instance2[m]
            r += "-" + instance2_item[1] + "(" + instance2_item[2] + ")"
        result.append(r)
    return " ".join(result)