Book Image

Python Natural Language Processing Cookbook

By : Zhenya Antić
Book Image

Python Natural Language Processing Cookbook

By: Zhenya Antić

Overview of this book

Python is the most widely used language for natural language processing (NLP) thanks to its extensive tools and libraries for analyzing text and extracting computer-usable data. This book will take you through a range of techniques for text processing, from basics such as parsing the parts of speech to complex topics such as topic modeling, text classification, and visualization. Starting with an overview of NLP, the book presents recipes for dividing text into sentences, stemming and lemmatization, removing stopwords, and parts of speech tagging to help you to prepare your data. You’ll then learn ways of extracting and representing grammatical information, such as dependency parsing and anaphora resolution, discover different ways of representing the semantics using bag-of-words, TF-IDF, word embeddings, and BERT, and develop skills for text classification using keywords, SVMs, LSTMs, and other techniques. As you advance, you’ll also see how to extract information from text, implement unsupervised and supervised techniques for topic modeling, and perform topic modeling of short texts, such as tweets. Additionally, the book shows you how to develop chatbots using NLTK and Rasa and visualize text data. By the end of this NLP book, you’ll have developed the skills to use a powerful set of tools for text processing.
Table of Contents (10 chapters)

Creating actions for the Rasa chatbot

In this recipe, we will add a custom action and greet the user by name.

Getting ready

In order to create custom actions, we will need to install the rasa_core_sdk package:

pip install rasa_core_sdk

How to do it…

We will first edit the configuration files, adding necessary information. Then, we will edit the actions.py file, which programs the necessary actions. We will then start the actions server and test the chatbot:

  1. First, in the domain.yml file, add a special intent called inform that may contain entities. The section will now look like this:
    intents:
      - greet
      - goodbye
      - affirm
      - deny
      - mood_great
      - mood_unhappy
      - bot_challenge
      - hours
      - address
      - thanks
      - inform
  2. In the same file, add a new section called entities where name is the entity:
    entities:
      - name
  3. Add a...