def __init__(self, files = [], dirs = []):
    self.dirs = dirs
    self.files = files
    self.files_by_lower_basename = {}
    for f in files:
      bn = os.path.basename(f).lower()
      if self.files_by_lower_basename not in bn:
        self.files_by_lower_basename[bn] = []
      self.files_by_lower_basename[bn].append(f)
dataset/ETHPy150Open natduca/quickopen/src/query_test.py/FakeDBShardManager.__init__/swapped operands of `not in`