from mpi4py import MPI
import sys

myrank = MPI.COMM_WORLD.Get_rank()
nprocs = MPI.COMM_WORLD.Get_size()
if myrank == 0:
    sys.stdout.write("Running on %d processes\n" %(nprocs))

sys.stdout.write ("Greetings from process %d\n" % (myrank))
MPI.Disconnect()