Case in point: `scipy.fftpack.convolve` namespace. It comes from a standalone Cython source, https://github.com/scipy/scipy/blob/main/scipy/fftpack/meson.build#L1, and its contents is not included into `scipy.fftpack namespace`, https://github.com/scipy/scipy/blob/main/scipy/fftpack/__init__.py