docs: def restoredata(filename=None):
      """Restore the state of the credolib workspace from a pickle file."""
      if filename is None:
          filename = 'credolib_state.pickle'
      ns = get_ipython().user_ns
      with open(filename, 'rb') as f:
          d = pickle.load(f)
      for k in d.keys():
          ns[k] = d[k]