from anytree.importer import DictImporter
from anytree.search import findall
from anytree import Node

def check(a: str, b: str, tree: dict) -> bool:
    root = DictImporter(nodecls=Node).import_(tree)
    nodes = findall(root, filter_=lambda node: node.name in (a, b))

    # idk what to do if there are more than 2 nodes...
    if len(nodes) != 2:
        return False

    # checks if the nodes are parent-child related
    if nodes[0].parent == nodes[1] or nodes[1].parent == nodes[0]:
        return True

    return False

# -------------

tree = {
        "name": "1",
        "children": [
            {
                "name": "2",
                "children": [
                    {
                        "name": "2.1",
                        "children": [{"name": "3"}]
                    },
                    {
                        "name": "2.2",
                        "children": [
                            {
                                "name": "2.2.1",
                                "children": [{"name": "3"}]
                            }
                        ]
                    }
                ]
            }
        ]
    }

# results in False
print(check(a="2.1", b="3", tree))