Make sima run on python 3 and numpy 1.26

[neurodroid]

Some changes that were required to install sima & pass tests on
MacOS 15.3.1 x86_64
Python 3.13.2 from MacPorts
numpy 1.26.4 from MacPorts
Test results:

>>> sima.test()
NumPy version 1.26.4
NumPy relaxed strides checking option: True
NumPy CPU features:  SSE SSE2 SSE3 SSSE3* SSE41* POPCNT* SSE42* AVX* F16C* FMA3* AVX2* AVX512F? AVX512CD? AVX512_KNL? AVX512_SKX? AVX512_CLX? AVX512_CNL? AVX512_ICL?
..........................................................................................................................................                    [100%]
138 passed, 1 deselected in 1.41s
True