def METHOD_NAME(self):
    if os.name == 'posix':
        r, w, e = popen2.popen3([self.cmd])
        self.validate_output(self.teststr, self.expected, r, w, e)
    r, w, e = popen2.popen3(self.cmd)
    self.validate_output(self.teststr, self.expected, r, w, e)