ImportError: No module named yaml - ROS NOETIC

[Zolubas]

Hello!
I got the following error using ros noetic on ubuntu20

File "/opt/ros/noetic/lib/python3/dist-packages/genpy/message.py", line 48, in
import yaml
ImportError: No module named yaml

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I tryed install pyyaml usisng pip install pyyaml, pip3 install pyyaml and the error persists.
I tried a lot to find a solution for it in stackoverflow and etc but nothing works.
Thanks!