Tensorflow tutorial estimator Failed to convert object of type <type 'dict'> to Tensor - tensorflow

Question

I am running the tutorial code A Guide to TF Layers: Building a Convolutional Neural Network on API r.1.3
https://www.tensorflow.org/tutorials/layers
My code is here.
https://gist.github.com/Po-Hsuan-Huang/91e31d59fd3aa07f40272b75fe2a924d
The error shows:
runfile('/Users/pohsuanhuang/Documents/workspace/tensorflow_models/NMIST/cnn_mnist.py', wdir='/Users/pohsuanhuang/Documents/workspace/tensorflow_models/NMIST')
Extracting MNIST-data/train-images-idx3-ubyte.gz
Extracting MNIST-data/train-labels-idx1-ubyte.gz
Extracting MNIST-data/t10k-images-idx3-ubyte.gz
Extracting MNIST-data/t10k-labels-idx1-ubyte.gz
INFO:tensorflow:Using default config.
INFO:tensorflow:Using config: {'_save_checkpoints_secs': 600, '_session_config': None, '_keep_checkpoint_max': 5, '_tf_random_seed': 1, '_keep_checkpoint_every_n_hours': 10000, '_log_step_count_steps': 100, '_save_checkpoints_steps': None, '_model_dir': '/tmp/mnist_convnet_model', '_save_summary_steps': 100}
Traceback (most recent call last):
File "<ipython-input-1-c9b70e26f791>", line 1, in <module>
runfile('/Users/pohsuanhuang/Documents/workspace/tensorflow_models/NMIST/cnn_mnist.py', wdir='/Users/pohsuanhuang/Documents/workspace/tensorflow_models/NMIST')
File "/Users/pohsuanhuang/miniconda/envs/tensorflow/lib/python2.7/site-packages/spyder/utils/site/sitecustomize.py", line 866, in runfile
execfile(filename, namespace)
File "/Users/pohsuanhuang/miniconda/envs/tensorflow/lib/python2.7/site-packages/spyder/utils/site/sitecustomize.py", line 94, in execfile
builtins.execfile(filename, *where)
File "/Users/pohsuanhuang/Documents/workspace/tensorflow_models/NMIST/cnn_mnist.py", line 129, in <module>
main(None)
File "/Users/pohsuanhuang/Documents/workspace/tensorflow_models/NMIST/cnn_mnist.py", line 117, in main
hooks=[logging_hook])
File "/Users/pohsuanhuang/miniconda/envs/tensorflow/lib/python2.7/site-packages/tensorflow/python/estimator/estimator.py", line 241, in train
loss = self._train_model(input_fn=input_fn, hooks=hooks)
File "/Users/pohsuanhuang/miniconda/envs/tensorflow/lib/python2.7/site-packages/tensorflow/python/estimator/estimator.py", line 630, in _train_model
model_fn_lib.ModeKeys.TRAIN)
File "/Users/pohsuanhuang/miniconda/envs/tensorflow/lib/python2.7/site-packages/tensorflow/python/estimator/estimator.py", line 615, in _call_model_fn
model_fn_results = self._model_fn(features=features, **kwargs)
File "/Users/pohsuanhuang/Documents/workspace/tensorflow_models/NMIST/cnn_mnist.py", line 24, in cnn_model_fn
input_layer = tf.reshape(features, [-1, 28, 28, 1])
File "/Users/pohsuanhuang/miniconda/envs/tensorflow/lib/python2.7/site-packages/tensorflow/python/ops/gen_array_ops.py", line 2619, in reshape
name=name)
File "/Users/pohsuanhuang/miniconda/envs/tensorflow/lib/python2.7/site-packages/tensorflow/python/framework/op_def_library.py", line 493, in apply_op
raise err
TypeError: Failed to convert object of type <type 'dict'> to Tensor. Contents: {'x': <tf.Tensor 'random_shuffle_queue_DequeueMany:1' shape=(100, 784) dtype=float32>}. Consider casting elements to a supported type.
I traced down a little bit, and found the function estimator._call_input_fn() does not use parameter 'mode' at all, thus not able to create a tuple comprises features and labels. Is it the tutorial that needs to be modified, or there is some problem with this function. I don't understand why mode is unused here.
Thanks !
def _call_input_fn(self, input_fn, mode):
"""Calls the input function.
Args:
input_fn: The input function.
mode: ModeKeys
Returns:
Either features or (features, labels) where features and labels are:
features - `Tensor` or dictionary of string feature name to `Tensor`.
labels - `Tensor` or dictionary of `Tensor` with labels.
Raises:
ValueError: if input_fn takes invalid arguments.
"""
del mode # unused
input_fn_args = util.fn_args(input_fn)
kwargs = {}
if 'params' in input_fn_args:
kwargs['params'] = self.params
if 'config' in input_fn_args:
kwargs['config'] = self.config
with ops.device('/cpu:0'):
return input_fn(**kwargs)

Answer 1

Your gist doesn't actually contain any of your code... Either way, from your error message I think you have just mistranscribed a bit of code from the tutorial.
Your error log indicates you have
"/Users/pohsuanhuang/Documents/workspace/tensorflow_models/NMIST/cnn_mnist.py", line 24, in cnn_model_fn
input_layer = tf.reshape(features, [-1, 28, 28, 1])
Whereas the tutorial has:
input_layer = tf.reshape(features["x"], [-1, 28, 28, 1])