text: UNBALANCE_RATIO = 3
  
  # symbols
  UNEVEN = "uneven"
  MIN_CLASS = "min_class"
  MAX_CLASS = "max_class"
  CLASS_NUM = "class_num"
  EACH_CLASS_NUM = "each_class_num"
  NUM = "num"
  INDEX = "index"
  INDICES = "indices"
  CLASS_INFO = "each_class_info"
  SAMPLE_INFO = "sample_info"
  ITER_NUM = "iter_num"
  TRAIN_NUM = "train_num"
  TEST_NUM = "test_num"
  
  # CONSTANT NUMBER
  MAX_SAMPLE_NUM = 3000
  MIN_SAMPLE_NUM = 1000
  MAX_VALID_PERCLASS_SAMPLE = 200
  MAX_VALID_SET_SIZE = 500
  MIN_VALID_PER_CLASS = 1
  
  # MODEL HYPER PARAMETERS
  MODEL_FIRST_MAX_RUN_LOOP = 3
  MODEL_MAX_RUN_LOOP = 20
  
  # Modified by qmc
  NUM_MFCC = 96  # num of mfcc features, default value is 24
  MAX_AUDIO_DURATION = 6  # limited length of audio, like 20s
  
  FIRST_ROUND_DURATION = 10
  MIDDLE_DURATION = 15
  SECOND_ROUND_DURATION = 30
  
  IS_CUT_AUDIO = True
  AUDIO_SAMPLE_RATE = 16000
  MAX_FRAME_NUM = 700
  FFT_DURATION = 0.1
  HOP_DURATION = 0.04
  