The library error occurs because Nimpy cannot find libpython. This means that either `libpython.so` (assuming Linux) is missing or not in LD_LIBRARY_PATH (again, assuming Linux). If it's not installed, you can usually run `sudo apt-get install libpython3-dev` (or whatever package manager you use) if libpython is not installed. If it's installed, then make sure the location of the library is in LD_LIBRARY_PATH
Could be also that you're running some odd version of libpython that is not supported by Nimpy (very unlikely).
