get_nodes_between_nodes_in_tree_2.py

import ete3

def get_node_pos(node):
    if node.up is None:
        return 0
    pos = node.up.children.index(node)
    return pos
  
  
def post_traverse_from_node(node1, is_leaf_fn=None, node_end=None):
    to_visit = [(node1, 0)]
    pos = get_node_pos(node1)
    pos += 1
    node1_ancestors = set(node1.get_ancestors() + [node1])

    if is_leaf_fn is not None:
        _leaf = is_leaf_fn
    else:
        _leaf = node1.__class__.is_leaf

    while to_visit:
        node, pos = to_visit.pop(-1)
        try:
            node = node[1]
        except TypeError:
            # PREORDER ACTIONS
            if node in node1_ancestors and node.up:
                pos_new = get_node_pos(node)
                to_visit.append((node.up, pos_new + 1))
            if not _leaf(node):
                # ADD CHILDREN
                nodes_to_add = node.children
                if pos:
                    nodes_to_add = nodes_to_add[pos:]
                to_visit.extend(
                    zip(
                        reversed(node.children + [[1, node]]),
                        np.zeros(len(nodes_to_add) + 1)
                    )
                )
            else:
                yield node
        else:
            #POSTORDER ACTIONS
            yield node
        if node_end and node == node_end:
            break
  



if __name__ == "__main__":
  
  t = ete3.Tree('(((a,b)I1, (c,d)I2)I3, (e,(f,g)I4)I5);', format=1)
  node1 = t&"a"
  node_end = t&"f"

  ancestors = set(node1.get_ancestors()) | set(node_end.get_ancestors())

  def is_leaf_fn(node2):
      return node2 not in ancestors

  result_list = [n for n in post_traverse_from_node(node1, is_leaf_fn=is_leaf_fn, node_end=node_end)]