Python Process Info

Pipe the output of one process into the input of another via python:
import subprocess
p1 = subprocess.Popen(['echo','joe'], shell=False, stdout=subprocess.PIPE)
p2 = subprocess.Popen(['cat','-n'],
    stdin=p1.stdout, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
p2.stdout.read()

# Or 
out,err=p2.communicate()

Pipe standard input to a program
import subprocess
p1 = subprocess.Popen(['node', 'index.js'], shell=False,
    stdin=subprocess.PIPE, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
stdout, stderr = p1.communicate('standard input here')
p1.returncode

Convenience method for splitting apart shell commands for use in the above:
>>> import shlex
>>> shlex.split('ps -ef')
['ps', '-ef']