"""
训练脚本包

- dataset.py:          CRNNDataset / CaptchaDataset 通用数据集类
- train_utils.py:      CTC 训练通用逻辑 (train_ctc_model)
- train_normal.py:     训练普通字符识别 (LiteCRNN - normal)
- train_math.py:       训练算式识别 (LiteCRNN - math)
- train_3d.py:         训练 3D 立体识别 (ThreeDCNN)
- train_classifier.py: 训练调度分类器 (CaptchaClassifier)
"""