python feed STDIN to Popen process

stdinToPopen.py

#!/usr/bin/env python
from subprocess import Popen, PIPE
import shlex

items = ['i1', 'i2', 'i3']

cmd='xargs -rn1 -I% echo "run for %"'
p = Popen(shlex.split(cmd), stdout=PIPE, stdin=PIPE, stderr=PIPE)

# this will emulate the shell sequence: "echo 'i1 i2 i3'|tr ' ' '\n'|xargs ..."
(p_stdout, p_stderr) = p.communicate(input=b'\n'.join(items))
#...