Runtime ErrorAll platformsWeasyPrint < 53 · Pillow 10+

AttributeError: 'super' object has no attribute 'transform'

pip install weasyprint
from weasyprint import HTML
HTML(string="<p>Hello</p>").write_pdf("out.pdf")
AttributeError: 'super' object has no attribute 'transform'
File ".../PIL/ImageCms.py", line ..." in apply_transform
super().transform(...)
Why this happens

Pillow 10.0 removed the Image.ANTIALIAS constant and restructured the transform API. WeasyPrint versions before 53.0 call internal Pillow methods that no longer exist in Pillow 10+, causing AttributeError at render time.

Observed in
Any · WeasyPrint <53 + Pillow 10+
crashes
Any · WeasyPrint 53+ + Pillow 10+
ok
Any · WeasyPrint <53 + Pillow 9.x
ok (old Pillow)
Fixes
1Upgrade WeasyPrint to 53+Easiest

WeasyPrint 53.0 updated its Pillow integration to be compatible with Pillow 10+. Upgrade both packages together.

pip install --upgrade weasyprint pillow
2Pin Pillow to 9.x (temporary)Alternative

If upgrading WeasyPrint is not immediately possible, pin Pillow to the last 9.x release. Pillow 9.x is no longer receiving security updates — migrate as soon as practical.

pip install "pillow<10.0"
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Observed in 27 searches · Last verified Aug 2026
AttributeError: 'super' object has no attribute 'transform' — weasyprint