Backward compatible upgrade to fix deprecation warnings concerning Lo…

…oseVersion and pkg_resources for Python3.8+ (#1058)

* upgraded version checking to fix deprecation warnings

Removed usage of pgk_resources and distutils.version.LooseVersion

* < python3.8 backward compatible version checking

* Compacter version checking.

---------

Co-authored-by: glopezdiest <[email protected]>

scenario_runner.py

@@ -20,15 +20,28 @@
 import argparse
 from argparse import RawTextHelpFormatter
 from datetime import datetime
-from distutils.version import LooseVersion
+try:
+    from packaging.version import Version
+except ImportError:
+    from distutils.version import LooseVersion as Version # Python 2 fallback
 import importlib
 import inspect
 import os
 import signal
 import sys
 import time
 import json
-import pkg_resources
+
+try:
+    # requires Python 3.8+
+    from importlib.metadata import metadata
+    def get_carla_version():
+        return Version(metadata("carla")["Version"])
+except ModuleNotFoundError:
+    # backport checking for older Python versions; module is deprecated
+    import pkg_resources
+    def get_carla_version():
+        return Version(pkg_resources.get_distribution("carla").version)
 
 import carla
 
@@ -46,6 +59,9 @@
 # Version of scenario_runner
 VERSION = '0.9.13'
 
+# Minimum version of CARLA that is required
+MIN_CARLA_VERSION = '0.9.15'
+
 
 class ScenarioRunner(object):
 
@@ -91,9 +107,9 @@ def __init__(self, args):
         # requests in the localhost at port 2000.
         self.client = carla.Client(args.host, int(args.port))
         self.client.set_timeout(self.client_timeout)
-        dist = pkg_resources.get_distribution("carla")
-        if LooseVersion(dist.version) < LooseVersion('0.9.15'):
-            raise ImportError("CARLA version 0.9.15 or newer required. CARLA version found: {}".format(dist))
+        carla_version = get_carla_version()
+        if carla_version < Version(MIN_CARLA_VERSION):
+            raise ImportError("CARLA version {} or newer required. CARLA version found: {}".format(MIN_CARLA_VERSION, carla_version))
 
         # Load agent if requested via command line args
         # If something goes wrong an exception will be thrown by importlib (ok here)