NameError: name 'SumTree' is not defined

[apurva1210]

Hello,
I am getting this error when i try to run DeepC4.ipynb on google colabs.

NameError                                 Traceback (most recent call last)
<ipython-input-32-31c2879a102a> in <module>()
     24                  "batch_size":64, "gamma":0.90, "n_step":11}
     25 
---> 26 p1 = QPlayer(1, game, **player_config)
     27 p2 = MinimaxC4Player(2, game, epsilon=0)
     28 env = Environment(game, p1, p2)

1 frames
/content/qPlayer.py in __init__(self, name, game, **kwargs)
     23         self.updateTNEvery = kwargs['updateTNEvery'] if 'updateTNEvery' in kwargs else 4000
     24 
---> 25         self.memory = PMemory(self.mem_size) if 'memory' not in kwargs else kwargs['memory']
     26         self.goodMemory = PMemory(self.mem_size) if 'goodMemory' not in kwargs else kwargs['goodMemory']
     27 

/content/pMemory.py in __init__(self, capacity)
      9         self.e = 0.01
     10         self.a = 0.6
---> 11         self.tree = SumTree(capacity)
     12         self.cnt = 0
     13 

NameError: name 'SumTree' is not defined