custom parser not recognized after installation

[biosbob]

i've asked this question on stackoverflow, in case someone is accumulating reputation points....

i've developed and tested a custom pygments lexer, as described here... i then prepared a pyproject.toml file whose contents are as follows:

[build-system]
requires = ["setuptools"]
build-backend = "setuptools.build_meta"

[project]
name = "my-lexer"
version = "0.0.1"
dependencies = ["Pygments"]

[pygments.lexers]
dummy = "pkg.mylexer:MyLexer"

i then python -m build the project and pip install dist/*.tar.gz the generated output.... using pip list, i can see both pygments and my own package installed in the same environment....

as a test, i'll run pygmentize -L but don't see my custom language listed; attempts to force use of the lexer through the -l option likewise fail....

is there some obvious step i'm missing???? when/how does pygments discover my plugin??? is there some way i can trace that discovery process???