1. install openmpi instead of mpich, Open MPI 4.0.3/4.0.4 works for me - I always got “mpi4py libmpi.so.12: cannot open shared object file: no such file or directory” error message when using mpich. Check your mpi use mpirun --version for ubuntu.
  2. Create a clean environmemt, python version 3.9.16 and 3.11.4 work for me
  3. conda install -c conda-forge mpi4py
  4. Test your MPI and mpi4py use script: ``` import mpi4py from mpi4py import MPI

comm = MPI.COMM_WORLD rank = comm.Get_rank() print(‘My rank is ‘,rank) ``` In command line use mpirun -n 4 python name_of_your_script.py