RuntimeError: Graph is finalized and cannot be modified

[youthM]

An error when running train.py

File "D:\Program Files\Anaconda3\envs\tensorflow\lib\site-packages\spyder\utils\site\sitecustomize.py", line 705, in runfile
execfile(filename, namespace)
File "D:\Program Files\Anaconda3\envs\tensorflow\lib\site-packages\spyder\utils\site\sitecustomize.py", line 102, in execfile
exec(compile(f.read(), filename, 'exec'), namespace)
File "E:/SRGAN-master/train.py", line 23, in
data = tf.sg_data.Mnist(batch_size=batch_size)
File "D:\Program Files\Anaconda3\envs\tensorflow\lib\site-packages\sugartensor\sg_data.py", line 54, in init
_data_to_tensor([_train.images, _train.labels.astype('int32')], batch_size, name='train')
File "D:\Program Files\Anaconda3\envs\tensorflow\lib\site-packages\sugartensor\sg_data.py", line 22, in _data_to_tensor
const_list = [tf.constant(data) for data in data_list]
File "D:\Program Files\Anaconda3\envs\tensorflow\lib\site-packages\sugartensor\sg_data.py", line 22, in
const_list = [tf.constant(data) for data in data_list]
File "D:\Program Files\Anaconda3\envs\tensorflow\lib\site-packages\tensorflow\python\framework\constant_op.py", line 220, in constant
name=name).outputs[0]
File "D:\Program Files\Anaconda3\envs\tensorflow\lib\site-packages\tensorflow\python\framework\ops.py", line 3246, in create_op
self._check_not_finalized()
File "D:\Program Files\Anaconda3\envs\tensorflow\lib\site-packages\tensorflow\python\framework\ops.py", line 2880, in _check_not_finalized
raise RuntimeError("Graph is finalized and cannot be modified.")
RuntimeError: Graph is finalized and cannot be modified.