Update Cython sources

Author: dalcinl

mpi4py_fft/fftw/fftw_xfftn.pxd

@@ -1,3 +1,4 @@
+# cython: language_level=3str
 cdef extern from "fftw3.h" nogil:
 
     ctypedef struct fftw_complex_struct:
@@ -57,4 +58,4 @@ cdef extern from "fftw_planxfftn.h" nogil:
                              int      kind[],
                              unsigned flags)
 
-ctypedef void (*generic_function)(void *plan, void *_in, void *_out) nogil
+ctypedef void (*generic_function)(void *plan, void *_in, void *_out) noexcept nogil

mpi4py_fft/fftw/fftw_xfftn.pyx

@@ -1,4 +1,4 @@
-#cython: language_level=3
+# cython: language_level=3str
 from . cimport fftw_xfftn
 cimport numpy as np
 from .utilities import *

mpi4py_fft/fftw/utilities.pyx

@@ -1,4 +1,4 @@
-#cython: language_level=3
+#cython: language_level=3str
 
 cimport numpy as np
 import numpy as np

setup.py

@@ -79,7 +79,13 @@ def get_fftw_libs():
 
 def generate_extensions(fftwlibs, force=True):
     """Generate files with float and long double"""
-    from distutils.dep_util import newer_group
+    try:
+        from setuptools.modified import newer_group
+    except ImportError:
+        try:
+            from setuptools.dep_util import newer_group
+        except ImportError:
+            from distutils.dep_util import newer_group
 
     for d in fftwlibs:
         if d == 'double':