libact: Pool-based Active Learning in Python

libact is a python package designed to make active learning easier for real-world users. The package not only implements several popular active learning strategies, but also features the active learning by learning meta-strategy that allows the machine to automatically learn the best strategy on the fly. The package is designed for easy extension in terms of strategies, models and labelers. In particular, libact models can be easily obtained by interfacing with the models in scikit-learn.