Don't use deprecated distutils module.

satpy/writers/cf_writer.py

@@ -145,11 +145,11 @@
 import warnings
 from collections import OrderedDict, defaultdict
 from datetime import datetime
-from distutils.version import LooseVersion
 
 import numpy as np
 import xarray as xr
 from dask.base import tokenize
+from packaging.version import Version
 from pyresample.geometry import AreaDefinition, SwathDefinition
 from xarray.coding.times import CFDatetimeCoder
 
@@ -199,7 +199,7 @@
 def create_grid_mapping(area):
     """Create the grid mapping instance for `area`."""
     import pyproj
-    if LooseVersion(pyproj.__version__) < LooseVersion('2.4.1'):
+    if Version(pyproj.__version__) < Version('2.4.1'):
         # technically 2.2, but important bug fixes in 2.4.1
         raise ImportError("'cf' writer requires pyproj 2.4.1 or greater")
     # let pyproj do the heavily lifting

setup.py

@@ -33,7 +33,7 @@
 requires = ['numpy >=1.13', 'pillow', 'pyresample >=1.24.0', 'trollsift',
             'trollimage >=1.20', 'pykdtree', 'pyyaml >=5.1', 'xarray >=0.10.1, !=0.13.0',
             'dask[array] >=0.17.1', 'pyproj>=2.2', 'zarr', 'donfig', 'appdirs',
-            'pooch', 'pyorbital']
+            'packaging', 'pooch', 'pyorbital']
 
 test_requires = ['behave', 'h5py', 'netCDF4', 'pyhdf', 'imageio',
                  'rasterio', 'geoviews', 'trollimage', 'fsspec', 'bottleneck',