/usr/lib/python3/dist-packages/crispy_forms/templates/bootstrap4/layout/button.html is in python3-django-crispy-forms 1.7.0-1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 | <button {{ button.flat_attrs|safe }}>{{ button.content|safe }}</button>
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