[ROS2][Conda] conda environment to install ROS2 on Mac

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I have been struggling to install ROS2 in a conda environment on Mac.

I have tried to do:
conda create -n ros2 anaconda
conda activate ros2
conda install -c conda-forge rosdep rospkg

I got many errors When I run ros2:
such as Library not loaded, No module named 'em', No module named 'lxml'

It seems I still do not have enough packages for running ros2, either rosdep or rospkg is for ROS1.
Is there a proper conda package for ROS2? Is there anyone using conda environment for ROS2? I did not find much information by googling.