def _setup(self, cmd):
        self.cmd = cmd
        self.pid = self._popen.pid
        self.tochild = self._popen.stdin
        self.fromchild = self._popen.stdout
        self.childerr = self._popen.stderr
Setup the Popen attributes.
dataset/ETHPy150Open azoft-dev-team/imagrium/env/Lib/popen2.py/Popen3._setup