Provide own getargspec for roles and modules with Python 3.11

Python 3.11 dropped compat inspect.getargspec. As the roles and modules
need to support Python2 and Python3, the code for getargspec has been
copied from Python 3.10 and is added as a fallback as soon as getargspec
can not be imported from inspect. The copied getargspec is using
getfullargspec internally.

Fixes: #855 (Python's inspect.getargspec was removed in version 3.11)

plugins/module_utils/ansible_freeipa_module.py

@@ -29,7 +29,7 @@ __all__ = ["gssapi", "netaddr", "api", "ipalib_errors", "Env",
            "DEFAULT_CONFIG", "LDAP_GENERALIZED_TIME_FORMAT",
            "kinit_password", "kinit_keytab", "run", "DN", "VERSION",
            "paths", "get_credentials_if_valid", "Encoding",
-           "load_pem_x509_certificate", "DNSName"]
+           "load_pem_x509_certificate", "DNSName", "getargspec"]
 
 import sys
 
@@ -48,7 +48,28 @@ else:
     import gssapi
     from datetime import datetime
     from contextlib import contextmanager
-    import inspect
+
+    # Import getargspec from inspect or provide own getargspec for
+    # Python 2 compatibility with Python 3.11+.
+    try:
+        from inspect import getargspec
+    except ImportError:
+        from collections import namedtuple
+        from inspect import getfullargspec
+
+        # The code is copied from Python 3.10 inspect.py
+        # Authors: Ka-Ping Yee <ping@lfw.org>
+        #          Yury Selivanov <yselivanov@sprymix.com>
+        ArgSpec = namedtuple('ArgSpec', 'args varargs keywords defaults')
+
+        def getargspec(func):
+            args, varargs, varkw, defaults, kwonlyargs, _kwonlydefaults, \
+                ann = getfullargspec(func)
+            if kwonlyargs or ann:
+                raise ValueError(
+                    "Function has keyword-only parameters or annotations"
+                    ", use inspect.signature() API which can support them")
+            return ArgSpec(args, varargs, varkw, defaults)
 
     # ansible-freeipa requires locale to be C, IPA requires utf-8.
     os.environ["LANGUAGE"] = "C"
@@ -1228,7 +1249,7 @@ else:
             elif result_handler is not None:
                 if "errors" not in handlers_user_args:
                     # pylint: disable=deprecated-method
-                    argspec = inspect.getargspec(result_handler)
+                    argspec = getargspec(result_handler)
                     if "errors" in argspec.args:
                         handlers_user_args["errors"] = _errors