[PYTHON] How to count the number of elements in Django and output to a template

Introduction

I want to count all the elements in a Django template and display them like "how many"

Conclusion

Django's built-in template tags and filters Use {{value | length}}

Example)template.html


<h3>Bookshelf({{ books|length }})</h3>

From the browser スクリーンショット 2020-10-13 18.13.46.png Is displayed.

I knew that Rubu on Rails could display it with <% = Objects.all%>, but Django's It took a lot of time to avoid the word built-in tag.

References

https://docs.djangoproject.com/ja/3.1/ref/templates/builtins/#ref-templates-builtins-filters

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