How to say if a word tree is similar to another? - python-3.x

Question

I want to know when a tree is similar to part of another, for instance when
When did Beyonce start becoming popular?
is partly included in the following sentences :
She started becoming popular in the late 1990s (1st case)
She rose to fame in the late 1990s (2nd case)
I am able to say when one text is strictly included included in another : I created a class that transforms spaCy array to tree and I show later how to transform text to spaCy.
class WordTree:
'''Tree for spaCy dependency parsing array'''
def __init__(self, tree, is_subtree=False):
"""
Construct a new 'WordTree' object.
:param array: The array contening the dependency
:param parent: The parent of the array if exists
:return: returns nothing
"""
self.parent = []
self.children = []
self.data = tree.label().split('_')[0] # the first element of the tree # We are going to add the synonyms as well.
for subtree in tree:
if type(subtree) == Tree:
# Iterate through the depth of the subtree.
t = WordTree(subtree, True)
t.parent=tree.label().split('_')[0]
elif type(subtree) == str:
surface_form = subtree.split('_')[0]
self.children.append(surface_form)
And I can tell when one sentence is included in another tahnks to the following functions :
def isSubtree(T,S):
if S is None:
return True
if T is None:
return False
if areIdentical(T, S):
return True
return any(isSubtree(c, S) for c in T.children)
def areIdentical(root1, root2):
'''
function to say if two roots are identical
'''
# Base Case
if root1 is None and root2 is None:
return True
if root1 is None or root2 is None:
return False
# Check if the data of both roots their and children are the same
return (root1.data == root2.data and
((areIdentical(child1 , child2))
for child1, child2 in zip(root1.children, root2.children)))
Indeed, for instance :
# first tree creation
text = "start becoming popular"
textSpacy = spacy_nlp(text)
treeText = nltk_spacy_tree(textSpacy)
t = WordTree(treeText[0])
# second tree creation
question = "When did Beyonce start becoming popular?"
questionSpacy = spacy_nlp(question)
treeQuestion = nltk_spacy_tree(questionSpacy)
q = WordTree(treeQuestion[0])
# tree comparison
isSubtree(t,q)
Returns True. Therefore when can I say that a tree is partly included (1st case) in another or similar (2nd case) to another ?