Question

! gcc -O3 -bundle -undefined dynamic_lookup c_fib.c -o ctypes_fib.so

# For Unix systmes
# ! gcc -O3 -fPIC -shared -std=c99  c_fib.c -o ctypes_fib.so

from ctypes import CDLL, c_int, c_double

def ctypes_fib(n):

    # Use ctypes to load the library
    lib = CDLL('./ctypes_fib.so')

    # We need to give the argument and return types explicitly
    lib.c_fib.argtypes = [c_int]
    lib.c_fib.restype  = c_double

    return lib.c_fib(n)

ctypes_fib(10)

55.0000