MPI_map.py

from mpi4py import MPI

comm = MPI.COMM_WORLD # All our nodes in this cluster
rank = comm.Get_rank() # Our node's "ID"

if rank == 0: # If we're the root/base node, we'll be the one distributing the data
    data = [1,2,3,4,5] 
else:
    data = []

#Scatter our list elements evenly across the node in comm
data = comm.scatter(data, root=0)
print "rank", rank, "recieved", data
data = data + 2 # Perform our mapping function

#Gather
data = comm.gather(data, root=0) # Send all the mapped data back to our root node

comm.Barrier() # Wait until all processes reach this point

if rank == 0: # Only our root node had the data gathered to it
    print data