class subprocess.Popen( args, 
   bufsize=0, 
   executable=None,
   stdin=None,
   stdout=None, 
   stderr=None, 
   preexec_fn=None, 
   close_fds=False, 
   shell=False, 
   cwd=None, 
   env=None, 
   universal_newlines=False, 
   startupinfo=None, 
   creationflags=0)

subprocess.Popen(["gedit","abc.txt"])
subprocess.Popen("gedit abc.txt")

subprocess.Popen("gedit abc.txt", shell=True)

subprocess.Popen(["/bin/sh", "-c", "gedit abc.txt"])

subprocess.Popen(["notepad.exe", "abc.txt"])
subprocess.Popen("notepad.exe abc.txt")

subprocess.Popen("notepad.exe abc.txt" shell=True)

subprocess.Popen("cmd.exe /C "+"notepad.exe abc.txt" shell=True)

subprocess.call*

def call(*popenargs, **kwargs):
  return Popen(*popenargs, **kwargs).wait()

def check_call(*popenargs, **kwargs):
  retcode = call(*popenargs, **kwargs)
  if retcode:
    cmd = kwargs.get("args")
    raise CalledProcessError(retcode, cmd)
  return 0

def check_output(*popenargs, **kwargs):
  process = Popen(*popenargs, stdout=PIPE, **kwargs)
  output, unused_err = process.communicate()
  retcode = process.poll()
  if retcode:
    cmd = kwargs.get("args")
    raise CalledProcessError(retcode, cmd, output=output)
  return output