Revert "FIX python-lz4 version comparison (joblib#847)"

This reverts commit efe896a.

conftest.py

@@ -1,4 +1,4 @@
-from pkg_resources import parse_version
+from distutils.version import LooseVersion
 
 import pytest
 from _pytest.doctest import DoctestItem
@@ -25,7 +25,7 @@ def pytest_collection_modifyitems(config, items):
             # numpy changed the str/repr formatting of numpy arrays in 1.14.
             # We want to run doctests only for numpy >= 1.14.
             import numpy as np
-            if parse_version(np.__version__) >= parse_version('1.14'):
+            if LooseVersion(np.__version__) >= LooseVersion('1.14'):
                 skip_doctests = False
         except ImportError:
             pass

joblib/backports.py

@@ -6,7 +6,7 @@
 import ctypes
 import sys
 
-from pkg_resources import parse_version
+from distutils.version import LooseVersion
 
 try:
     import numpy as np
@@ -21,7 +21,7 @@ def make_memmap(filename, dtype='uint8', mode='r+', offset=0,
         """
         mm = np.memmap(filename, dtype=dtype, mode=mode, offset=offset,
                        shape=shape, order=order)
-        if parse_version(np.__version__) < parse_version('1.13'):
+        if LooseVersion(np.__version__) < '1.13':
             mm.offset = offset
         return mm
 except ImportError:

joblib/compressor.py

@@ -3,7 +3,7 @@
 import sys
 import io
 import zlib
-from pkg_resources import parse_version
+from distutils.version import LooseVersion
 
 from ._compat import _basestring, PY3_OR_LATER
 
@@ -226,9 +226,7 @@ def _check_versions(self):
             raise ValueError('lz4 compression is only available with '
                              'python3+.')
 
-        if lz4 is None or (
-            parse_version(lz4.__version__) < parse_version('0.19')
-        ):
+        if lz4 is None or LooseVersion(lz4.__version__) < LooseVersion('0.19'):
             raise ValueError(LZ4_NOT_INSTALLED_ERROR)
 
     def compressor_file(self, fileobj, compresslevel=None):