docs: def md(cls, data, force_field, temperature, nsteps,
             other_settings=None):
          """
          Example for a simple MD run based on template md.txt.
  
          Args:
              data (LammpsData or str): Data file as a LammpsData
                  instance or path to an existing data file.
              force_field (str): Combined force field related cmds. For
                  example, 'pair_style eam\npair_coeff * * Cu_u3.eam'.
              temperature (float): Simulation temperature.
              nsteps (int): No. of steps to run.
              other_settings (dict): other settings to be filled into
                  placeholders.
  
          """
          template_path = os.path.join(cls.template_dir, "md.txt")
          with open(template_path) as f:
              script_template = f.read()
          settings = other_settings.copy() if other_settings is not None else {}
          settings.update({'force_field': force_field,
                           "temperature": temperature, "nsteps": nsteps})
          script_filename = "in.md"
          return cls(script_template=script_template,
                     settings=settings, data=data, script_filename=script_filename)