from fastai import *        # Quick access to most common functionality
from fastai.text import *   # Quick access to NLP functionality

path = untar_data(URLs.IMDB_SAMPLE)
path

df = pd.read_csv(path/'train.csv', header=None)
df.head()

classes = read_classes(path/'classes.txt')
classes[0], classes[1]

data_lm = TextLMDataBunch.from_csv(path)
data_clas = TextClasDataBunch.from_csv(path, vocab=data_lm.train_ds.vocab)

learn = RNNLearner.language_model(data_lm, pretrained_model=URLs.WT103)
learn.unfreeze()
learn.fit(2, slice(1e-4,1e-2))

learn.save_encoder('enc')

learn = RNNLearner.classifier(data_clas)
learn.load_encoder('enc')
learn.fit(3, 1e-3)