invoke bash commands in python3.6

runbash.py

#!/usr/bin/env python 
from __future__ import print_function
__author__ = 'github.com/ruxi'
__license__= 'MIT'
import sys
import os.path
import subprocess
def runbash(cmd, cwd=".", shell=True, logname="runbash.log", ioprint=True):
    """
    cmd: bash command to run. example: 'ls -l'
    cwd: working directory of child process
    logname: (optional)
       - logname is name of log file
       - False to turn off logging
    ioprint: (optional)
       - print output to py terminal
    """
    # make cwd if not exist
    if sys.version_info > (3,0,0): 
        os.makedirs(cwd, exist_ok=True)
     
    # invoke bash process
    process = subprocess.Popen(cmd, shell=shell
                     , stdout=subprocess.PIPE
                     , stderr=subprocess.STDOUT
                     , bufsize=1
                     , cwd=cwd)
    
    # standard output
    if logname:
        filename = os.path.join(cwd, logname)
        logfile = open(filename, 'w')
        
    for line in iter(process.stdout):
        msg = line.decode()
        if ioprint:
            print(msg, end='')
        if logname:
            logfile.write(msg)

might be compatible with 2.7