https://www.kaggle.com/c/text-normalization-challenge-russian-language

Convert text from written expressions into spoken forms.

Look to pipeline.py to see main transform chain for text. Solution uses Bi-directional LSTM with Attention (Keras/Tensorflow), XGBoost, a lot of dictionaries and other tricks.

My position on the private leaderboard is only 29th, but this last solution would give a little more.