code: def run(self):
          
          lammps_cmd = self.lammps_bin + ['-in', self.input_filename]
          print("Running: {}".format(" ".join(lammps_cmd)))
          p = Popen(lammps_cmd, stdout=PIPE, stderr=PIPE)
          (stdout, stderr) = p.communicate()
          return stdout, stderr
docs: Write the input/data files and run LAMMPS.