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.

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)