Summarizing videos in 300 lines of code

Laurent Picard
Google Cloud - Community
13 min readMay 30, 2020

⏳ 2021–10–08 update

  • Updated GitHub version with latest library versions + Python 3.7 → 3.9

👋 Hello!

Dear developers,

Do you like the adage “a picture is worth a thousand words”? I do! Let’s check if it also works for “a picture is worth a thousand frames”.

In this tutorial, you’ll see the following:

  • how to understand the content of a video in a blink,
  • in less than 300 lines of Python (3.7) code.
Video summary example
A visual summary generated from a 2'42" video made of 35 sequences (shots). The summary is a grid where each cell is a frame representing a video shot.

🔭 Objectives

This tutorial has 2 objectives, 1 practical and 1 technical:

  1. Automatically generate visual summaries of videos
  2. Build a processing pipeline with these properties:
  • managed (always ready and easy to set up)
  • scalable (able to ingest several videos in parallel)
  • not costing anything when not used

🛠️ Tools

A few tools are enough:

  • Storage space for videos and results
  • A serverless solution to run the code
  • A machine learning model to analyze videos
  • A library to extract frames from videos
  • A library to generate the visual summaries

🧱 Architecture

Here is a possible architecture using 3 Google Cloud services (Cloud Storage, Cloud Functions, and Video Intelligence API):

Architecture

The processing pipeline follows these steps:

  1. You upload a video to the 1st bucket (a bucket is a storage space in the cloud)
  2. The upload event automatically triggers the 1st function
  3. The function sends a request to the Video Intelligence API to detect the shots
  4. The Video Intelligence API analyzes the video and uploads the results (annotations) to the 2nd bucket
  5. The upload event triggers the 2nd function
  6. The function downloads both annotation and video files
  7. The function renders and uploads the summary to the 3rd bucket
  8. The video summary is ready!

🐍 Python libraries

Open source client libraries let you interface with Google Cloud services in idiomatic Python. You’ll use the following:

Cloud Storage

Video Intelligence API

Here is a choice of 2 additional Python libraries for the graphical needs:

OpenCV

Pillow

⚙️ Project setup

Assuming you have a Google Cloud account, you can set up the architecture from Cloud Shell with the gcloud and gsutil commands. This lets you script everything from scratch in a reproducible way.

Environment variables

# Project
PROJECT_NAME="Visual Summary"
PROJECT_ID="visual-summary-REPLACE_WITH_UNIQUE_SUFFIX"
# Cloud Storage region (https://cloud.google.com/storage/docs/locations)
GCS_REGION="europe-west1"
# Cloud Functions region (https://cloud.google.com/functions/docs/locations)
GCF_REGION="europe-west1"
# Source
GIT_REPO="cherry-on-py"
PROJECT_SRC=~/$PROJECT_ID/$GIT_REPO/gcf_video_summary

# Cloud Storage buckets (environment variables)
export VIDEO_BUCKET="b1-videos_${PROJECT_ID}"
export ANNOTATION_BUCKET="b2-annotations_${PROJECT_ID}"
export SUMMARY_BUCKET="b3-summaries_${PROJECT_ID}"

Note: You can use your GitHub username as a unique suffix.

New project

gcloud projects create $PROJECT_ID \
--name="$PROJECT_NAME" \
--set-as-default
Create in progress for [https://cloudresourcemanager.googleapis.com/v1/projects/PROJECT_ID].
Waiting for [operations/cp...] to finish...done.
Enabling service [cloudapis.googleapis.com] on project [PROJECT_ID]...
Operation "operations/acf..." finished successfully.
Updated property [core/project] to [PROJECT_ID].

Billing account

# Link project with billing account (single account)
BILLING_ACCOUNT=$(gcloud beta billing accounts list \
--format 'value(name)')

# Link project with billing account (specific one among multiple accounts)
BILLING_ACCOUNT=$(gcloud beta billing accounts list \
--format 'value(name)' \
--filter "displayName='My Billing Account'")

gcloud beta billing projects link $PROJECT_ID --billing-account $BILLING_ACCOUNT
billingAccountName: billingAccounts/XXXXXX-YYYYYY-ZZZZZZ
billingEnabled: true
name: projects/PROJECT_ID/billingInfo
projectId: PROJECT_ID

Buckets

# Create buckets with uniform bucket-level access
gsutil mb -b on -c regional -l $GCS_REGION gs://$VIDEO_BUCKET
gsutil mb -b on -c regional -l $GCS_REGION gs://$ANNOTATION_BUCKET
gsutil mb -b on -c regional -l $GCS_REGION gs://$SUMMARY_BUCKET
Creating gs://VIDEO_BUCKET/...
Creating gs://ANNOTATION_BUCKET/...
Creating gs://SUMMARY_BUCKET/...

You can check how it looks like in the Cloud Console:

Cloud Storage buckets

Service account

Create a service account. This is for development purposes only (not needed for production). This provides you with credentials to run your code locally.

mkdir ~/$PROJECT_ID
cd ~/$PROJECT_ID

SERVICE_ACCOUNT_NAME="dev-service-account"
SERVICE_ACCOUNT="${SERVICE_ACCOUNT_NAME}@${PROJECT_ID}.iam.gserviceaccount.com"
gcloud iam service-accounts create $SERVICE_ACCOUNT_NAME
gcloud iam service-accounts keys create ~/$PROJECT_ID/key.json --iam-account $SERVICE_ACCOUNT
Created service account [SERVICE_ACCOUNT_NAME].
created key [...] of type [json] as [~/PROJECT_ID/key.json] for [SERVICE_ACCOUNT]

Set the GOOGLE_APPLICATION_CREDENTIALS environment variable and check that it points to the service account key. When you run the application code in the current shell session, client libraries will use these credentials for authentication. If you open a new shell session, set the variable again.

export GOOGLE_APPLICATION_CREDENTIALS=~/$PROJECT_ID/key.json
cat $GOOGLE_APPLICATION_CREDENTIALS
{
"type": "service_account",
"project_id": "PROJECT_ID",
"private_key_id": "...",
"private_key": "-----BEGIN PRIVATE KEY-----\n...",
"client_email": "SERVICE_ACCOUNT",
...
}

Authorize the service account to access the buckets:

IAM_BINDING="serviceAccount:${SERVICE_ACCOUNT}:roles/storage.objectAdmin"
gsutil iam ch $IAM_BINDING gs://$VIDEO_BUCKET
gsutil iam ch $IAM_BINDING gs://$ANNOTATION_BUCKET
gsutil iam ch $IAM_BINDING gs://$SUMMARY_BUCKET

APIs

A few APIs are enabled by default:

gcloud services listNAME                              TITLE
bigquery.googleapis.com BigQuery API
bigquerystorage.googleapis.com BigQuery Storage API
cloudapis.googleapis.com Google Cloud APIs
clouddebugger.googleapis.com Cloud Debugger API
cloudtrace.googleapis.com Cloud Trace API
datastore.googleapis.com Cloud Datastore API
logging.googleapis.com Cloud Logging API
monitoring.googleapis.com Cloud Monitoring API
servicemanagement.googleapis.com Service Management API
serviceusage.googleapis.com Service Usage API
sql-component.googleapis.com Cloud SQL
storage-api.googleapis.com Google Cloud Storage JSON API
storage-component.googleapis.com Cloud Storage

Enable the Video Intelligence and Cloud Functions APIs:

gcloud services enable \
videointelligence.googleapis.com \
cloudfunctions.googleapis.com
Operation "operations/acf..." finished successfully.

Source code

Retrieve the source code:

cd ~/$PROJECT_ID
git clone
https://github.com/PicardParis/$GIT_REPO.git
Cloning into 'GIT_REPO'...
...

🧠 Video analysis

Video shot detection

The Video Intelligence API is a pre-trained machine learning model that can analyze videos. One of the multiple features is video shot detection. For the 1st Cloud Function, here is a possible core function calling annotate_video() with the SHOT_CHANGE_DETECTION feature:

Local development and tests

Before deploying the function, you need to develop and test it. Create a Python 3 virtual environment and activate it:

cd ~/$PROJECT_ID
python3 -m venv venv
source venv/bin/activate

Install the dependencies:

pip install -r $PROJECT_SRC/gcf1_detect_shots/requirements.txt

Check the dependencies:

pip listPackage                        Version
------------------------------ ----------
...
google-cloud-storage 1.28.1
google-cloud-videointelligence 1.14.0
...

You can use the main scope to test the function in script mode:

Note: You have already exported the ANNOTATION_BUCKET environment variable earlier in the shell session; you will also define it later at deployment stage. This makes the code generic and lets you reuse it independently of the output bucket.

Test the function:

VIDEO_PATH="cloud-samples-data/video/gbikes_dinosaur.mp4"
VIDEO_URI="gs://$VIDEO_PATH"
python $PROJECT_SRC/gcf1_detect_shots/main.py $VIDEO_URI
Launching shot detection for <gs://cloud-samples-data/video/gbikes_dinosaur.mp4>...

Note: The test video <gbikes_dinosaur.mp4> is located in an external bucket. This works because the video is publicly accessible.

Wait a moment and check that the annotations have been generated:

gsutil ls -r gs://$ANNOTATION_BUCKET964  YYYY-MM-DDThh:mm:ssZ  gs://ANNOTATION_BUCKET/VIDEO_PATH.json
TOTAL: 1 objects, 964 bytes (964 B)

Check the last 200 bytes of the annotation file:

gsutil cat -r -200 gs://$ANNOTATION_BUCKET/$VIDEO_PATH.json}
}, {
"start_time_offset": {
"seconds": 28,
"nanos": 166666000
},
"end_time_offset": {
"seconds": 42,
"nanos": 766666000
}
} ]
} ]
}

Note: Those are the start and end positions of the last video shot. Everything seems fine.

Clean up when you’re finished:

gsutil rm gs://$ANNOTATION_BUCKET/$VIDEO_PATH.json

deactivate

rm -rf venv

Function entry point

Note: This function will be called whenever a video is uploaded to the bucket defined as a trigger.

Function deployment

Deploy the 1st function:

GCF_NAME="gcf1_detect_shots"
GCF_SOURCE="$PROJECT_SRC/gcf1_detect_shots"
GCF_ENTRY_POINT="gcf_detect_shots"
GCF_TRIGGER_BUCKET="$VIDEO_BUCKET"
GCF_ENV_VARS="ANNOTATION_BUCKET=$ANNOTATION_BUCKET"
GCF_MEMORY="128MB"

gcloud functions deploy $GCF_NAME \
--runtime python37 \
--source $GCF_SOURCE \
--entry-point $GCF_ENTRY_POINT \
--update-env-vars $GCF_ENV_VARS \
--trigger-bucket $GCF_TRIGGER_BUCKET \
--region $GCF_REGION \
--memory $GCF_MEMORY \
--quiet

Note: The default memory allocated for a Cloud Function is 256 MB (possible values are 128MB, 256MB, 512MB, 1024MB, and 2048MB). As the function has no memory or CPU needs (it sends a simple API request), the minimum memory setting is enough.

Deploying function (may take a while - up to 2 minutes)...done.
availableMemoryMb: 128
entryPoint: gcf_detect_shots
environmentVariables:
ANNOTATION_BUCKET: b2-annotations...
eventTrigger:
eventType: google.storage.object.finalize
...
status: ACTIVE
timeout: 60s
updateTime: 'YYYY-MM-DDThh:mm:ss.mmmZ'
versionId: '1'

Note: The ANNOTATION_BUCKET environment variable is defined with the --update-env-vars flag. Using an environment variable lets you deploy the exact same code with different trigger and output buckets.

Here is how it looks like in the Cloud Console:

Cloud Functions

Production tests

Make sure to test the function in production. Copy a video into the video bucket:

VIDEO_NAME="gbikes_dinosaur.mp4"
SRC_URI="gs://
cloud-samples-data/video/$VIDEO_NAME"
DST_URI="gs://$VIDEO_BUCKET/$VIDEO_NAME"

gsutil cp $SRC_URI $DST_URI
Copying gs://cloud-samples-data/video/gbikes_dinosaur.mp4 [Content-Type=video/mp4]...
- [1 files][ 62.0 MiB/ 62.0 MiB]
Operation completed over 1 objects/62.0 MiB.

Query the logs to check that the function has been triggered:

gcloud functions logs read --region $GCF_REGIONLEVEL  NAME               EXECUTION_ID  TIME_UTC  LOG
D gcf1_detect_shots ... ... Function execution started
I gcf1_detect_shots ... ... Launching shot detection for <gs://VIDEO_BUCKET/VIDEO_NAME>...
D gcf1_detect_shots ... ... Function execution took 874 ms, finished with status: 'ok'

Wait a moment and check the annotation bucket:

gsutil ls -r gs://$ANNOTATION_BUCKET

You should see the annotation file:

gs://ANNOTATION_BUCKET/VIDEO_BUCKET/:
gs://ANNOTATION_BUCKET/VIDEO_BUCKET/VIDEO_NAME.json

The 1st function is operational!

🎞️ Visual Summary

Code structure

It’s interesting to split the code into 2 main classes:

  • StorageHelper for local file and cloud storage object management
  • VideoProcessor for graphical processings

Here is a possible core function:

Note: If exceptions are raised, it’s handy to log them with logging.exception() to get a stack trace in production logs.

Class StorageHelper

The class manages the following:

  • The retrieval and parsing of video shot annotations
  • The download of source videos
  • The upload of generated visual summaries
  • File names

The source video is handled in the with statement context manager:

Note: Once downloaded, the video uses memory space in the /tmp RAM disk (the only writable space for the serverless function). It's best to delete temporary files when they're not needed anymore, to avoid potential out-of-memory errors on future invocations of the function.

Annotations are retrieved with the methods storage.Blob.download_as_string() and json.loads():

The parsing is handled with this VideoShot helper class:

Video shot info can be exposed with a getter and a generator:

The naming convention was chosen to keep consistent object paths between the different buckets. This also lets you deduce the video path from the annotation URI:

The video is directly downloaded with storage.Blob.download_to_filename():

On the opposite, results can be uploaded with storage.Blob.upload_from_string():

Note: from_string means from_bytes here (Python 2 legacy). Pillow supports working with memory images, which avoids having to manage local files.

And finally, here is a possible naming convention for the summary files:

Class VideoProcessor

The class manages the following:

  • Video frame extraction
  • Visual summary generation

Opening and closing the video is handled in the with statement context manager:

The video summary is a grid of cells which can be rendered in a single loop with two generators:

Note: shot_ratio is set to 0.5 by default to extract video shot middle frames.

The first generator yields cell images:

The second generator yields cell positions:

OpenCV easily allows extracting video frames at a given position:

Choosing the summary grid composition is arbitrary. Here is an example to compose a summary preserving the video proportions:

Finally, Pillow gives full control on image serializations:

Note: Working with in-memory images avoids managing local files and uses less memory.

Local development and tests

You can use the main scope to test the function in script mode:

Test the function:

cd ~/$PROJECT_ID
python3 -m venv venv
source venv/bin/activate

pip install -r $PROJECT_SRC/gcf2_generate_summary/requirements.txt

VIDEO_NAME="gbikes_dinosaur.mp4"
ANNOTATION_URI="gs://$ANNOTATION_BUCKET/$VIDEO_BUCKET/$VIDEO_NAME.json"

python $PROJECT_SRC/gcf2_generate_summary/main.py $ANNOTATION_URI
Downloading -> /tmp/SUMMARY_BUCKET/VIDEO_BUCKET/VIDEO_NAME
Generating summary...
Uploading -> VIDEO_BUCKET/VIDEO_NAME.summary004.jpeg

Note: The uploaded video summary shows 4 shots.

Clean up:

deactivate
rm -rf venv

Function entry point

Note: This function will be called whenever an annotation file is uploaded to the bucket defined as a trigger.

Function deployment

GCF_NAME="gcf2_generate_summary"
GCF_SOURCE="$PROJECT_SRC/gcf2_generate_summary"
GCF_ENTRY_POINT="gcf_generate_summary"
GCF_TRIGGER_BUCKET="$ANNOTATION_BUCKET"
GCF_ENV_VARS="SUMMARY_BUCKET=$SUMMARY_BUCKET"
GCF_TIMEOUT="540s"
GCF_MEMORY="512MB"

gcloud functions deploy $GCF_NAME \
--runtime python37 \
--source $GCF_SOURCE \
--entry-point $GCF_ENTRY_POINT \
--update-env-vars $GCF_ENV_VARS \
--trigger-bucket $GCF_TRIGGER_BUCKET \
--region $GCF_REGION \
--timeout $GCF_TIMEOUT \
--memory $GCF_MEMORY \
--quiet

Notes:

  • The default timeout for a Cloud Function is 60 seconds. As you’re deploying a background function with potentially long processings, set it to the maximum value (540 seconds = 9 minutes).
  • You also need to bump up the memory a little for the video and image processings. Depending on the size of your videos and the maximum resolution of your output summaries, or if you need to generate the summary faster (memory size and vCPU speed are correlated), you might use a higher value (1024MB or 2048MB).
Deploying function (may take a while - up to 2 minutes)...done.
availableMemoryMb: 512
entryPoint: gcf_generate_summary
environmentVariables:
SUMMARY_BUCKET: b3-summaries...
...
status: ACTIVE
timeout: 540s
updateTime: 'YYYY-MM-DDThh:mm:ss.mmmZ'
versionId: '1'

Here is how it looks like in the Cloud Console:

Cloud Functions 2

Production tests

Make sure to test the function in production. You can upload an annotation file in the 2nd bucket:

VIDEO_NAME="gbikes_dinosaur.mp4"
ANNOTATION_FILE="$VIDEO_NAME.json"
ANNOTATION_URI="gs://$ANNOTATION_BUCKET/$VIDEO_BUCKET/$ANNOTATION_FILE"
gsutil cp $ANNOTATION_URI .
gsutil cp $ANNOTATION_FILE $ANNOTATION_URI
rm $ANNOTATION_FILE

Note: This reuses the previous local test annotation file and overwrites it. Overwriting a file in a bucket also triggers attached functions.

Wait a few seconds and query the logs to check that the function has been triggered:

gcloud functions logs read --region $GCF_REGIONLEVEL  NAME                   EXECUTION_ID  TIME_UTC  LOG
...
D gcf2_generate_summary ... ... Function execution started
I gcf2_generate_summary ... ... Downloading -> /tmp/SUMMARY_BUCKET/VIDEO_BUCKET/VIDEO_NAME
I gcf2_generate_summary ... ... Generating summary...
I gcf2_generate_summary ... ... Uploading -> VIDEO_BUCKET/VIDEO_NAME.summary004.jpeg
D gcf2_generate_summary ... ... Function execution took 11591 ms, finished with status: 'ok'

The 2nd function is operational and the pipeline is in place! You can now do end-to-end tests by copying new videos in the 1st bucket.

Results

Download the generated summary on your computer:

cd ~/$PROJECT_ID
gsutil cp -r gs://$SUMMARY_BUCKET/**.jpeg .
cloudshell download *.jpeg

Here is the visual summary for gbikes_dinosaur.mp4 (4 detected shots):

Visual summary for gbikes_dinosaur.mp4

You can also directly preview the file from the Cloud Console:

Video summary

🍒 Cherry on the Py 🐍

Now, the icing on the cake (or the “cherry on the pie” as we say in French)…

Based on the same architecture and code, you can add a few features:

  • Trigger the processing for videos from other buckets
  • Generate summaries in multiple formats (such as JPEG, PNG, WEBP)
  • Generate animated summaries (also in multiple formats, such as GIF, PNG, WEBP)

Enrich the architecture to duplicate 2 items:

  • The video shot detection function, to get it to run as an HTTP endpoint
  • The summary generation function to handle animated images

Adapt the code to support the new features:

  • An animated parameter to generate still or animated summaries
  • Save and upload the results in multiple formats

Architecture (v2)

Architecture (v2)
  • A. Video shot detection can also be triggered manually with an HTTP GET request
  • B. Still and animated summaries are generated in 2 functions in parallel
  • C. Summaries are uploaded in multiple image formats

HTTP entry point

Note: This is the same code as gcf_detect_shots with the video URI parameter provided from a GET request.

Function deployment

GCF_NAME="gcf1_detect_shots_http"
GCF_SOURCE="$PROJECT_SRC/gcf1_detect_shots"
GCF_ENTRY_POINT="gcf_detect_shots_http"
GCF_TRIGGER_BUCKET="$VIDEO_BUCKET"
GCF_ENV_VARS="ANNOTATION_BUCKET=$ANNOTATION_BUCKET"
GCF_MEMORY="128MB"

gcloud functions deploy $GCF_NAME \
--runtime python37 \
--source $GCF_SOURCE \
--entry-point $GCF_ENTRY_POINT \
--update-env-vars $GCF_ENV_VARS \
--trigger-http \
--region $GCF_REGION \
--memory $GCF_MEMORY \
--quiet

Here is how it looks like in the Cloud Console:

Cloud Functions 3

Animation support

Add an animated option in the core function:

Define the formats you’re interested in generating:

Add support to generate still and animated summaries in different formats:

The serialization can still take place in a single function:

Note: Pillow is both versatile and consistent, allowing for significant and clean code factorization.

Add an animated optional parameter to the StorageHelper class:

And finally, add an ANIMATED optional environment variable in the entry point:

Function deployment

Duplicate the 2nd function with the additional ANIMATED environment variable:

GCF_NAME="gcf2_generate_summary_animated"
GCF_SOURCE="$PROJECT_SRC/gcf2_generate_summary"
GCF_ENTRY_POINT="gcf_generate_summary"
GCF_TRIGGER_BUCKET="$ANNOTATION_BUCKET"
GCF_ENV_VARS1="SUMMARY_BUCKET=$SUMMARY_BUCKET"
GCF_ENV_VARS2="ANIMATED=1"
GCF_TIMEOUT="540s"
GCF_MEMORY="2048MB"

gcloud functions deploy $GCF_NAME \
--runtime python37 \
--source $GCF_SOURCE \
--entry-point $GCF_ENTRY_POINT \
--update-env-vars $GCF_ENV_VARS1 \
--update-env-vars $GCF_ENV_VARS2 \
--trigger-bucket $GCF_TRIGGER_BUCKET \
--region $GCF_REGION \
--timeout $GCF_TIMEOUT \
--memory $GCF_MEMORY \
--quiet

Here is how it looks like in the Cloud Console:

Cloud Functions 4

🎉 Final tests

The HTTP endpoint lets you trigger the pipeline with a GET request:

GCF_NAME="gcf1_detect_shots_http"
VIDEO_URI="gs://
cloud-samples-data/video/visionapi.mp4"
GCF_URL="https://$GCF_REGION-$PROJECT_ID.cloudfunctions.net/$GCF_NAME?video_uri=$VIDEO_URI"

curl $GCF_URL -H "Authorization: bearer $(gcloud auth print-identity-token)"
Launched shot detection for video_uri <VIDEO_URI>

Note: The test video <visionapi.mp4> is located in an external bucket but is publicly accessible.

In addition, copy one or several videos into the video bucket. You can drag and drop videos:

Dragging files to a bucket

The videos are then processed in parallel. Here are a few logs:

LEVEL NAME                           EXECUTION_ID ... LOG
...
D gcf2_generate_summary_animated f6n6tslsfwdu ... Function execution took 49293 ms, finished with status: 'ok'
I gcf2_generate_summary yd1vqabafn17 ... Uploading -> b1-videos.../JaneGoodall.mp4.summary035_still.png
I gcf2_generate_summary_animated qv9b03814jjk ... shot_ratio: 43%
I gcf2_generate_summary yd1vqabafn17 ... Uploading -> b1-videos.../JaneGoodall.mp4.summary035_still.webp
D gcf2_generate_summary yd1vqabafn17 ... Function execution took 54616 ms, finished with status: 'ok'
I gcf2_generate_summary_animated g4d2wrzxz2st ... shot_ratio: 71%
...
D gcf2_generate_summary amwmov1wk0gn ... Function execution took 65256 ms, finished with status: 'ok'
I gcf2_generate_summary_animated 7pp882fz0x84 ... shot_ratio: 57%
I gcf2_generate_summary_animated i3u830hsjz4r ... Uploading -> b1-videos.../JaneGoodall.mp4.summary035_anim.png
I gcf2_generate_summary_animated i3u830hsjz4r ... Uploading -> b1-videos.../JaneGoodall.mp4.summary035_anim.webp
D gcf2_generate_summary_animated i3u830hsjz4r ... Function execution took 70862 ms, finished with status: 'ok'
...

In the 3rd bucket, you’ll find all still and animated summaries:

Video summary

You’ve already seen the still summary for <JaneGoodall.mp4> as an introduction to this tutorial. In the animated version, and in only 6 frames, you get an even better idea of what the whole video is about:

Video summary

If you don’t want to keep your project, you can delete it:

gcloud projects delete $PROJECT_ID

➕ One more thing

first_line_after_licence=16
find $PROJECT_SRC -name '*.py' -exec tail -n +$first_line_after_licence {} \; | grep -v "^$" | wc -l
289

You did everything in under 300 lines of Python. Less lines, less bugs!

🔥🐍 Mission accomplished! 🐍🔥

🖖 See you

I hope you appreciated this tutorial and would love to read your feedback. You can also follow me on Twitter.

⏳ Updates

  • 2021–10–08: Updated GitHub version with latest library versions + Python 3.7 → 3.9

--

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Laurent Picard
Google Cloud - Community

Tech lover, passionate about software, hardware, science and anything shaping the future • ⛅ explorer at Google • Opinions my own