AttributeError: module 'tensorflow' has no attribute 'Session'
With the new version of python3.6 my problem is solved. 
I removed my previous python3.6 and installed the newest version. Then installed tensorflow through pip and it works.
When I call any function in python3.6, I get the error below; however, it works fine in python3.4. Any idea? 
import tensorflow as tf 
tf.Session()
Traceback (most recent call last):
  File "", line 1, in 
AttributeError: module 'tensorflow' has no attribute 'Session'

Here is my  System information


OS Platform and Distribution (e.g., Linux Ubuntu 16.04): Debian 8.7 
TensorFlow installed from (source or binary): by pip3
TensorFlow version (use command below): 1.7.0
Python version: 3.6.5
CUDA/cuDNN version: cuda 9.0 and cudnn 7.0
GPU model and memory: K80, 12 GB 
Exact command to reproduce:
import tensorflow as tf 
tf.Session()