```
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 != None and q != None:
if p.val != q.val:
return False
a = self.isSameTree(p.left,q.left)
b = self.isSameTree(p.right,q.right)
return a and b
```