Running flaml[tune] using "-O" flag for python interpreter (optimization - disables assertions) crashes #981

analysis = tune.run(
  File "/home/ec2-user/pyvenv/lib64/python3.9/site-packages/flaml/tune/tune.py", line 536, in run
    search_alg = SearchAlgorithm(
  File "/home/ec2-user/pyvenv/lib64/python3.9/site-packages/flaml/tune/searcher/blendsearch.py", line 248, in __init__
    points_to_evaluate=self._evaluated_points,
AttributeError: 'BlendSearch' object has no attribute '_evaluated_points'