LSTM for predicting text

Our first test for LSTM will be text prediction. Our network will learn the next word in a phrase, just like we had to do when we memorized a poem at school. Here, we just train it on a small poem, but if such a network was trained on a writer's full texts, with more capacity (so with more layers and probably larger ones), it could learn their style and write like the writer.

Let's store our fable:

text="""A slave named Androcles once escaped from his master and fled to the forest. As he was wandering about there he came upon a Lion lying down moaning and groaning. At first he turned to flee, but finding that the Lion did not pursue him, he turned back and went up to him.

As he came near, the Lion put out his paw, which was all swollen and bleeding, and Androcles found that a huge thorn had got into it, and was causing all the pain. He pulled out the thorn and bound up the paw of the Lion, who was soon able to rise and lick the hand of Androcles like a dog. Then the...