is_subtree.py

# Definition for a binary tree node.
class TreeNode(object):
    def __init__(self, val=0, left=None, right=None):
        self.val = val
        self.left = left
        self.right = right
class Solution(object):
    def isSameTree(self, p, q): #!RECURSION CODE
        """
        :type p: TreeNode
        :type q: TreeNode
        :rtype: bool
        """
        if not p and not q:
            return True
        if not p or not q or p.val != q.val:
            return False

        return(self.isSameTree(p.left,q.left) and self.isSameTree(p.right,q.right))

    def isSubtree(self, root, subRoot):
        """
        :type root: TreeNode
        :type subRoot: TreeNode
        :rtype: bool
        """
        if not subRoot :
            return True
        if not root:
            return False
        
        if self.isSameTree(root,subRoot):
            return True
        else:
            return(self.isSubtree(root.left,subRoot) or self.isSubtree(root.right,subRoot))