#!/usr/bin/python
# -*- coding: utf-8 -*-
import subprocess

def exec_cmd(cmd):
    proc = subprocess.Popen(
        cmd,
        shell=True,
        stdout=None,
        stderr=subprocess.STDOUT)

if __name__ == '__main__':
    exec_cmd('paste -d \'\t\' col1.txt col2.txt > paste.txt')
