new_contents: # Definition for a binary tree node.
  # class TreeNode(object):
  #     def __init__(self, x):
  #         self.val = x
  #         self.left = None
  #         self.right = None
  
  class Solution(object):
      def isSameTree(self, p, q):
          """
          :type p: TreeNode
          :type q: TreeNode
          :rtype: bool
          """
          if p == None and q == None:
              return True
              
          if p == None or q == None:
              return False
          
          if p.val != q.val:
              return False
              
          return self.isSameTree(p.left, q.left) and self.isSameTree(p.right, q.right)
  
subject: Create solution.py