1. Overview
The Natural Language API lets you extract information from unstructured text using Google machine learning. In this tutorial, you'll focus on using its Python client library.
What you'll learn
- How to set up your environment
- How to perform sentiment analysis
- How to perform entity analysis
- How to perform syntax analysis
- How to perform content classification
- How to perform text moderation
What you'll need
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2. Setup and requirements
Self-paced environment setup
- Sign-in to the Google Cloud Console and create a new project or reuse an existing one. If you don't already have a Gmail or Google Workspace account, you must create one.
- The Project name is the display name for this project's participants. It is a character string not used by Google APIs. You can always update it.
- The Project ID is unique across all Google Cloud projects and is immutable (cannot be changed after it has been set). The Cloud Console auto-generates a unique string; usually you don't care what it is. In most codelabs, you'll need to reference your Project ID (typically identified as
PROJECT_ID). If you don't like the generated ID, you might generate another random one. Alternatively, you can try your own, and see if it's available. It can't be changed after this step and remains for the duration of the project. - For your information, there is a third value, a Project Number, which some APIs use. Learn more about all three of these values in the documentation.
- Next, you'll need to enable billing in the Cloud Console to use Cloud resources/APIs. Running through this codelab won't cost much, if anything at all. To shut down resources to avoid incurring billing beyond this tutorial, you can delete the resources you created or delete the project. New Google Cloud users are eligible for the $300 USD Free Trial program.
Start Cloud Shell
While Google Cloud can be operated remotely from your laptop, in this codelab you will be using Cloud Shell, a command line environment running in the Cloud.
Activate Cloud Shell
- From the Cloud Console, click Activate Cloud Shell
.
If this is your first time starting Cloud Shell, you're presented with an intermediate screen describing what it is. If you were presented with an intermediate screen, click Continue.
It should only take a few moments to provision and connect to Cloud Shell.
This virtual machine is loaded with all the development tools needed. It offers a persistent 5 GB home directory and runs in Google Cloud, greatly enhancing network performance and authentication. Much, if not all, of your work in this codelab can be done with a browser.
Once connected to Cloud Shell, you should see that you are authenticated and that the project is set to your project ID.
- Run the following command in Cloud Shell to confirm that you are authenticated:
gcloud auth list
Command output
Credentialed Accounts
ACTIVE ACCOUNT
* <my_account>@<my_domain.com>
To set the active account, run:
$ gcloud config set account `ACCOUNT`
- Run the following command in Cloud Shell to confirm that the gcloud command knows about your project:
gcloud config list project
Command output
[core] project = <PROJECT_ID>
If it is not, you can set it with this command:
gcloud config set project <PROJECT_ID>
Command output
Updated property [core/project].
3. Environment setup
Before you can begin using the Natural Language API, run the following command in Cloud Shell to enable the API:
gcloud services enable language.googleapis.com
You should see something like this:
Operation "operations/..." finished successfully.
Now, you can use the Natural Language API!
Navigate to your home directory:
cd ~
Create a Python virtual environment to isolate the dependencies:
virtualenv venv-language
Activate the virtual environment:
source venv-language/bin/activate
Install IPython, Pandas, and the Natural Language API client library:
pip install ipython pandas tabulate google-cloud-language
You should see something like this:
... Installing collected packages: ... pandas ... ipython ... google-cloud-language Successfully installed ... google-cloud-language-2.11.0 ...
Now, you're ready to use the Natural Language API client library!
In the next steps, you'll use an interactive Python interpreter called IPython, which you installed in the previous step. Start a session by running ipython in Cloud Shell:
ipython
You should see something like this:
Python 3.9.2 (default, Feb 28 2021, 17:03:44) Type 'copyright', 'credits' or 'license' for more information IPython 8.15.0 -- An enhanced Interactive Python. Type '?' for help. In [1]:
4. Sentiment analysis
Sentiment analysis inspects the given text and identifies the prevailing emotional opinions within the text, especially to determine expressed sentiments as positive, negative, or neutral, both at the sentence and the document levels. It is performed with the analyze_sentiment method which returns an AnalyzeSentimentResponse.
Copy the following code into your IPython session:
from google.cloud import language
def analyze_text_sentiment(text: str) -> language.AnalyzeSentimentResponse:
client = language.LanguageServiceClient()
document = language.Document(
content=text,
type_=language.Document.Type.PLAIN_TEXT,
)
return client.analyze_sentiment(document=document)
def show_text_sentiment(response: language.AnalyzeSentimentResponse):
import pandas as pd
columns = ["score", "sentence"]
data = [(s.sentiment.score, s.text.content) for s in response.sentences]
df_sentence = pd.DataFrame(columns=columns, data=data)
sentiment = response.document_sentiment
columns = ["score", "magnitude", "language"]
data = [(sentiment.score, sentiment.magnitude, response.language)]
df_document = pd.DataFrame(columns=columns, data=data)
format_args = dict(index=False, tablefmt="presto", floatfmt="+.1f")
print(f"At sentence level:\n{df_sentence.to_markdown(**format_args)}")
print()
print(f"At document level:\n{df_document.to_markdown(**format_args)}")
Perform an analysis:
# Input
text = """
Python is a very readable language, which makes it easy to understand and maintain code.
It's simple, very flexible, easy to learn, and suitable for a wide variety of tasks.
One disadvantage is its speed: it's not as fast as some other programming languages.
"""
# Send a request to the API
analyze_sentiment_response = analyze_text_sentiment(text)
# Show the results
show_text_sentiment(analyze_sentiment_response)
You should see an output like the following:
At sentence level:
score | sentence
---------+------------------------------------------------------------------------------------------
+0.8 | Python is a very readable language, which makes it easy to understand and maintain code.
+0.9 | It's simple, very flexible, easy to learn, and suitable for a wide variety of tasks.
-0.4 | One disadvantage is its speed: it's not as fast as some other programming languages.
At document level:
score | magnitude | language
---------+-------------+------------
+0.4 | +2.2 | en
Take a moment to test your own sentences.
Summary
In this step, you were able to perform sentiment analysis on a string of text!
5. Entity analysis
Entity analysis inspects the given text for known entities (proper nouns such as public figures, landmarks, etc.), and returns information about those entities. It is performed with the analyze_entities method which returns an AnalyzeEntitiesResponse.
Copy the following code into your IPython session:
from google.cloud import language
def analyze_text_entities(text: str) -> language.AnalyzeEntitiesResponse:
client = language.LanguageServiceClient()
document = language.Document(
content=text,
type_=language.Document.Type.PLAIN_TEXT,
)
return client.analyze_entities(document=document)
def show_text_entities(response: language.AnalyzeEntitiesResponse):
import pandas as pd
columns = ("name", "type", "salience", "mid", "wikipedia_url")
data = (
(
entity.name,
entity.type_.name,
entity.salience,
entity.metadata.get("mid", ""),
entity.metadata.get("wikipedia_url", ""),
)
for entity in response.entities
)
df = pd.DataFrame(columns=columns, data=data)
print(df.to_markdown(index=False, tablefmt="presto", floatfmt=".0%"))
Perform an analysis:
# Input
text = """Guido van Rossum is best known as the creator of Python,
which he named after the Monty Python comedy troupe.
He was born in Haarlem, Netherlands.
"""
# Send a request to the API
analyze_entities_response = analyze_text_entities(text)
# Show the results
show_text_entities(analyze_entities_response)
You should see an output like the following:
name | type | salience | mid | wikipedia_url ------------------+--------------+------------+-----------+------------------------------------------------------------- Guido van Rossum | PERSON | 50% | /m/01h05c | https://en.wikipedia.org/wiki/Guido_van_Rossum Python | ORGANIZATION | 38% | /m/05z1_ | https://en.wikipedia.org/wiki/Python_(programming_language) creator | PERSON | 5% | | Monty Python | PERSON | 3% | /m/04sd0 | https://en.wikipedia.org/wiki/Monty_Python comedy troupe | PERSON | 2% | | Haarlem | LOCATION | 1% | /m/0h095 | https://en.wikipedia.org/wiki/Haarlem Netherlands | LOCATION | 1% | /m/059j2 | https://en.wikipedia.org/wiki/Netherlands
Take a moment to test your own sentences mentioning other entities.
Summary
In this step, you were able to perform entity analysis!
6. Syntax analysis
Syntax analysis extracts linguistic information, breaking up the given text into a series of sentences and tokens (generally based on word boundaries), providing further analysis on those tokens. It is performed with the analyze_syntax method which returns an AnalyzeSyntaxResponse.
Copy the following code into your IPython session:
from typing import Optional
from google.cloud import language
def analyze_text_syntax(text: str) -> language.AnalyzeSyntaxResponse:
client = language.LanguageServiceClient()
document = language.Document(
content=text,
type_=language.Document.Type.PLAIN_TEXT,
)
return client.analyze_syntax(document=document)
def get_token_info(token: Optional[language.Token]) -> list[str]:
parts = [
"tag",
"aspect",
"case",
"form",
"gender",
"mood",
"number",
"person",
"proper",
"reciprocity",
"tense",
"voice",
]
if not token:
return ["token", "lemma"] + parts
text = token.text.content
lemma = token.lemma if token.lemma != token.text.content else ""
info = [text, lemma]
for part in parts:
pos = token.part_of_speech
info.append(getattr(pos, part).name if part in pos else "")
return info
def show_text_syntax(response: language.AnalyzeSyntaxResponse):
import pandas as pd
tokens = len(response.tokens)
sentences = len(response.sentences)
columns = get_token_info(None)
data = (get_token_info(token) for token in response.tokens)
df = pd.DataFrame(columns=columns, data=data)
# Remove empty columns
empty_columns = [col for col in df if df[col].eq("").all()]
df.drop(empty_columns, axis=1, inplace=True)
print(f"Analyzed {tokens} token(s) from {sentences} sentence(s):")
print(df.to_markdown(index=False, tablefmt="presto"))
Perform an analysis:
# Input
text = """Guido van Rossum is best known as the creator of Python.
He was born in Haarlem, Netherlands.
"""
# Send a request to the API
analyze_syntax_response = analyze_text_syntax(text)
# Show the results
show_text_syntax(analyze_syntax_response)
You should see an output like the following:
Analyzed 20 token(s) from 2 sentence(s): token | lemma | tag | case | gender | mood | number | person | proper | tense | voice -------------+---------+-------+------------+-----------+------------+----------+----------+----------+---------+--------- Guido | | NOUN | | | | SINGULAR | | PROPER | | van | | NOUN | | | | SINGULAR | | PROPER | | Rossum | | NOUN | | | | SINGULAR | | PROPER | | is | be | VERB | | | INDICATIVE | SINGULAR | THIRD | | PRESENT | best | well | ADV | | | | | | | | known | know | VERB | | | | | | | PAST | as | | ADP | | | | | | | | the | | DET | | | | | | | | creator | | NOUN | | | | SINGULAR | | | | of | | ADP | | | | | | | | Python | | NOUN | | | | SINGULAR | | PROPER | | . | | PUNCT | | | | | | | | He | | PRON | NOMINATIVE | MASCULINE | | SINGULAR | THIRD | | | was | be | VERB | | | INDICATIVE | SINGULAR | THIRD | | PAST | born | bear | VERB | | | | | | | PAST | PASSIVE in | | ADP | | | | | | | | Haarlem | | NOUN | | | | SINGULAR | | PROPER | | , | | PUNCT | | | | | | | | Netherlands | | NOUN | | | | SINGULAR | | PROPER | | . | | PUNCT | | | | | | | |
Take a moment to test your own sentences with other syntactic structures.
If you dive deeper into the response insights, you'll also find the relationships between the tokens. Here is a visual interpretation showing the complete syntax analysis for this example, a screenshot from the online Natural Language demo:
Summary
In this step, you were able to perform syntax analysis!
7. Content classification
Content classification analyzes a document and returns a list of content categories that apply to the text found in the document. It is performed with the classify_text method which returns a ClassifyTextResponse.
Copy the following code into your IPython session:
from google.cloud import language
def classify_text(text: str) -> language.ClassifyTextResponse:
client = language.LanguageServiceClient()
document = language.Document(
content=text,
type_=language.Document.Type.PLAIN_TEXT,
)
return client.classify_text(document=document)
def show_text_classification(text: str, response: language.ClassifyTextResponse):
import pandas as pd
columns = ["category", "confidence"]
data = ((category.name, category.confidence) for category in response.categories)
df = pd.DataFrame(columns=columns, data=data)
print(f"Text analyzed:\n{text}")
print(df.to_markdown(index=False, tablefmt="presto", floatfmt=".0%"))
Perform an analysis:
# Input
text = """Python is an interpreted, high-level, general-purpose programming language.
Created by Guido van Rossum and first released in 1991, Python's design philosophy
emphasizes code readability with its notable use of significant whitespace.
"""
# Send a request to the API
classify_text_response = classify_text(text)
# Show the results
show_text_classification(text, classify_text_response)
You should see an output like the following:
Text analyzed: Python is an interpreted, high-level, general-purpose programming language. Created by Guido van Rossum and first released in 1991, Python's design philosophy emphasizes code readability with its notable use of significant whitespace. category | confidence --------------------------------------+-------------- /Computers & Electronics/Programming | 99% /Science/Computer Science | 99%
Take a moment to test your own sentences relating to other categories. Note that you must supply a text block (document) with at least twenty tokens (words and punctuation signs).
Summary
In this step, you were able to perform content classification!
8. Text moderation
Powered by Google's latest PaLM 2 foundation model, text moderation identifies a wide range of harmful content, including hate speech, bullying, and sexual harassment. It is performed with the moderate_text method which returns a ModerateTextResponse.
Copy the following code into your IPython session:
from google.cloud import language
def moderate_text(text: str) -> language.ModerateTextResponse:
client = language.LanguageServiceClient()
document = language.Document(
content=text,
type_=language.Document.Type.PLAIN_TEXT,
)
return client.moderate_text(document=document)
def show_text_moderation(text: str, response: language.ModerateTextResponse):
import pandas as pd
def confidence(category: language.ClassificationCategory) -> float:
return category.confidence
columns = ["category", "confidence"]
categories = sorted(response.moderation_categories, key=confidence, reverse=True)
data = ((category.name, category.confidence) for category in categories)
df = pd.DataFrame(columns=columns, data=data)
print(f"Text analyzed:\n{text}")
print(df.to_markdown(index=False, tablefmt="presto", floatfmt=".0%"))
Perform an analysis:
# Input
text = """I have to read Ulysses by James Joyce.
I'm a little over halfway through and I hate it.
What a pile of garbage!
"""
# Send a request to the API
response = moderate_text(text)
# Show the results
show_text_moderation(text, response)
You should see an output like the following:
Text analyzed: I have to read Ulysses by James Joyce. I'm a little over halfway through and I hate it. What a pile of garbage! category | confidence -----------------------+-------------- Toxic | 67% Insult | 58% Profanity | 53% Violent | 48% Illicit Drugs | 29% Religion & Belief | 27% Politics | 22% Death, Harm & Tragedy | 21% Finance | 18% Derogatory | 14% Firearms & Weapons | 11% Health | 10% Legal | 10% War & Conflict | 7% Public Safety | 5% Sexual | 4%
Take a moment to test your own sentences.
Summary
In this step, you were able to perform text moderation!
9. Congratulations!
You learned how to use the Natural Language API using Python!
Clean up
To clean up your development environment, from Cloud Shell:
- If you're still in your IPython session, go back to the shell:
exit - Stop using the Python virtual environment:
deactivate - Delete your virtual environment folder:
cd ~ ; rm -rf ./venv-language
To delete your Google Cloud project, from Cloud Shell:
- Retrieve your current project ID:
PROJECT_ID=$(gcloud config get-value core/project) - Make sure this is the project you want to delete:
echo $PROJECT_ID - Delete the project:
gcloud projects delete $PROJECT_ID
Learn more
- Test the demo in your browser: https://cloud.google.com/natural-language#natural-language-api-demo
- Natural Language documentation: https://cloud.google.com/natural-language/docs
- Python on Google Cloud: https://cloud.google.com/python
- Cloud Client Libraries for Python: https://github.com/googleapis/google-cloud-python
License
This work is licensed under a Creative Commons Attribution 2.0 Generic License.