Installing python-catkin-pkg on ros noetic

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I cannot install python catkin pkg on my Ubuntu 20.04 with ros noetic installed. I keep getting this error. I have done the sourcing of setup.bash already.

Appreciate any help. Thanks.

Reading package lists... Done
Building dependency tree       
Reading state information... Done
Package python-catkin-pkg is not available, but is referred to by another package.
This may mean that the package is missing, has been obsoleted, or
is only available from another source
However the following packages replace it:
  python3-catkin-pkg

E: Package 'python-catkin-pkg' has no installation candidate