numpy/f2py/_backends/__init__.py

def f2py_build_generator(name):
    if name == "meson":
        from ._meson import MesonBackend
        return MesonBackend
    elif name == "distutils":
        from ._distutils import DistutilsBackend
        return DistutilsBackend
    else:
        raise ValueError(f"Unknown backend: {name}")