The package name in the file name must be normalized

Author: warsaw

peps/pep-0829.rst

@@ -103,6 +103,10 @@ File Naming and Discovery
   Build backends and installers :ref:`**MAY** <tool-authors>` impose
   stricter constraints if they so choose.
 
+* The package name (i.e. the ``<package>`` prefix) **MUST** follow the
+  standard `name normalization rules
+  <https://packaging.python.org/en/latest/specifications/name-normalization/>`_.
+
 * ``<package>.site.toml`` files live in the same site-packages directories
   where ``<package>.pth`` files are found today.