<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def runproc(cmd):
 """ Convenience method for executing operating system commands. Accepts a single string that would be the command as executed on the command line. Returns a 2-tuple consisting of the output of (STDOUT, STDERR). In your code you should check for an empty STDERR output to determine if your command completed successfully. """

    proc = Popen([cmd], shell=True, stdin=PIPE, stdout=PIPE, stderr=PIPE,
            close_fds=True)
    stdoutdata, stderrdata = proc.communicate()
    return (stdoutdata, stderrdata)