def pipeline(*pipe_cmds, **kw):
    
    # Backup stdout, as it is for the last process in the pipeline only
    stdout = kw.get('stdout')

    # We're building first stages of the pipeline connected together
    kw['stdout'] = PIPE

    for cmd in pipe_cmds[:-1]:
        p = Popen(cmd, **kw)
        kw['stdin'] = p.stdout
        handles.append(p)
    
    # Restore backuped stdout for the last stage
    kw['stdout'] = stdout
    
    # End of the pipeline handled manually since we cannot reassign
    # p.stdout after Popen() call
    return Popen(pipe_cmds[-1], **kw)

pipeline(["/bin/ls"], ["/usr/bin/wc", "-l"]).communicate()