could not find a version that satisfies the requirement no matching distribution found for code example

Example 1: ERROR: Could not find a version that satisfies the requirement cv2 (from versions: none) ERROR: No matching distribution found for cv2

#Know the reason is really dumb, because the reason is that the package of CV2 is not called cv2 but called opencv-python

pip install opencv-python

#For python3:
pip3 install opencv-python

Example 2: ERROR: Could not find a version that satisfies the requirement tensorflow (from versions: none) ERROR: No matching distribution found for tensorflow

in the terminal paste this
this will surely work

pip3 install --upgrade https://storage.googleapis.com/tensorflow/mac/cpu/tensorflow-1.0.0-py3-none-any.whl