mitogen: Guard importlib imports with sys.version_info

Reduce number of doomed mitogen.core.Importer GET_MODULE requests from e.g.
Python 2.x contexts. Simplify work of static type checkers, LSPs, etc.

ansible_mitogen/module_finder.py

@@ -36,12 +36,10 @@ import os
 import re
 import sys
 
-try:
-    # Python >= 3.4, PEP 451 ModuleSpec API
+if sys.version_info >= (3, 4):
     import importlib.machinery
     import importlib.util
-except ImportError:
-    # Python < 3.4, PEP 302 Import Hooks
+else:
     import imp
 
 import mitogen.imports

ansible_mitogen/runner.py

@@ -52,20 +52,17 @@ import tempfile
 import traceback
 import types
 
+if sys.version_info >= (3, 4):
+    import importlib.machinery
+else:
+    import imp
+
 from ansible.module_utils.six.moves import shlex_quote
 
 import mitogen.core
 import ansible_mitogen.target  # TODO: circular import
 from mitogen.core import to_text
 
-try:
-    # Python >= 3.4, PEP 451 ModuleSpec API
-    import importlib.machinery
-    import importlib.util
-except ImportError:
-    # Python < 3.4, PEP 302 Import Hooks
-    import imp
-
 try:
     # Cannot use cStringIO as it does not support Unicode.
     from StringIO import StringIO

mitogen/core.py

@@ -96,12 +96,10 @@ else:
         if blocking:    fcntl.fcntl(fd, fcntl.F_SETFL, fl & ~os.O_NONBLOCK)
         else:           fcntl.fcntl(fd, fcntl.F_SETFL, fl | os.O_NONBLOCK)
 
-try:
-    # Python >= 3.4, PEP 451 ModuleSpec API
+if sys.version_info >= (3, 4):
     import importlib.machinery
     import importlib.util
-except ImportError:
-    # Python < 3.4, PEP 302 Import Hooks
+else:
     import imp
 
 if sys.version_info >= (2, 5):

mitogen/master.py

@@ -50,9 +50,7 @@ import zlib
 if sys.version_info >= (3, 7):
     import importlib.resources
 
-try:
-    # Python >= 3.4, PEP 451 ModuleSpec API
-    import importlib.machinery
+if sys.version_info >= (3, 4):
     import importlib.util
     from _imp import is_builtin as _is_builtin
 
@@ -66,8 +64,7 @@ try:
             return maybe_spec.loader
         except AttributeError:
             return None
-except ImportError:
-    # Python < 3.4, PEP 302 Import Hooks
+else:
     import imp
     from imp import is_builtin as _is_builtin