ValueError: No group keys passed! on Lucas simulation

[sbenthall]

$ python simulate/run_any_simulation.py output/20230127_ls
localhost rpc_queue 0 25 2 60 MockMarket UsualExpectations LUCAS0 5.0 0.96 1.000628 0.011988 0.05 1500 0.1 0.1 60.0 60.0 0.5 0 0 None
Traceback (most recent call last):
  File "/home/sb/projects/ufm/SHARKFin/simulate/run_any_simulation.py", line 301, in <module>
    data, sim_stats, history, class_stats = run_attention_simulation(
  File "/home/sb/projects/ufm/SHARKFin/simulate/run_any_simulation.py", line 140, in run_attention_simulation
    sim.simulate(burn_in = pad)
  File "/home/sb/projects/ufm/SHARKFin/sharkfin/simulation.py", line 740, in simulate
    self.track(-1)
  File "/home/sb/projects/ufm/SHARKFin/sharkfin/simulation.py", line 613, in track
    self.history['class_stats'].append(self.pop.class_stats(store=False))
  File "/home/sb/projects/ufm/SHARKFin/sharkfin/population.py", line 210, in class_stats
    agent_data.groupby(self.ex_ante_hetero_params)
  File "/home/sb/projects/ufm/SHARKFin/sharkfin-env/lib/python3.10/site-packages/pandas/core/frame.py", line 7718, in groupby
    return DataFrameGroupBy(
  File "/home/sb/projects/ufm/SHARKFin/sharkfin-env/lib/python3.10/site-packages/pandas/core/groupby/groupby.py", line 882, in __init__
    grouper, exclusions, obj = get_grouper(
  File "/home/sb/projects/ufm/SHARKFin/sharkfin-env/lib/python3.10/site-packages/pandas/core/groupby/grouper.py", line 910, in get_grouper
    raise ValueError("No group keys passed!")
ValueError: No group keys passed!