def run(self):
        """
        Perform the actual VASP run.

        Returns:
            (subprocess.Popen) Used for monitoring.
        """
        cmd = list(self.vasp_cmd)
        if self.auto_gamma:
            vi = VaspInput.from_directory(".")
            kpts = vi["KPOINTS"]
            if kpts.style == Kpoints.supported_modes.Gamma \
                    and tuple(kpts.kpts[0]) == (1, 1, 1):
                if self.gamma_vasp_cmd != None and which(
                        self.gamma_vasp_cmd[-1]):
                    cmd = self.gamma_vasp_cmd
                elif which(cmd[-1] + ".gamma"):
                    cmd[-1] += ".gamma"
        logging.info("Running {}".format(" ".join(cmd)))
        with open(self.output_file, 'w') as f:
            p = subprocess.Popen(cmd, stdout=f)
        return p
dataset/ETHPy150Open materialsproject/custodian/custodian/vasp/jobs.py/VaspJob.run/operator `is not` -> `!=`