Tensorflow problem

I use windows 7 with python 3.8.7, trying to operate tensorflow (pip list shows 2.12.0), when I operate "import tensorflow as tf" without errors, actually it does not recognize for instance :
model = tf.keras.models.Sequential() (renders AttributeError: module 'tensorflow' has no attribute 'keras')

or even : tf.__version__ (renders NameError: name 'tf' is not defined)