code: def get_default_options(num_machines=1, max_wallclock_seconds=1800, withmpi=False):
      
      return {
          'resources': {
              'num_machines': int(num_machines)
          },
          'max_wallclock_seconds': int(max_wallclock_seconds),
          'withmpi': withmpi,
      }
docs: Return an instance of the options dictionary with the minimally required parameters
      for a JobCalculation and set to default values unless overriden
  
      :param num_machines: set the number of nodes, default=1
      :param max_wallclock_seconds: set the maximum number of wallclock seconds, default=1800
      :param withmpi: if True the calculation will be run in MPI mode