Remove legacy distutils support.

Signed-off-by: Anders Kaseorg <anders@zulip.com>

zulip_botserver/setup.py

@@ -1,15 +1,13 @@
 #!/usr/bin/env python3
 
-import sys
-from typing import Any, Dict, Optional
+from setuptools import find_packages, setup
 
 ZULIP_BOTSERVER_VERSION = "0.8.1"
 
 with open("README.md") as fh:
     long_description = fh.read()
 
-# We should be installable with either setuptools or distutils.
-package_info = dict(
+setup(
     name="zulip_botserver",
     version=ZULIP_BOTSERVER_VERSION,
     description="Zulip's Flask server for running bots",
@@ -42,48 +40,10 @@ package_info = dict(
     },
     test_suite="tests",
     package_data={"zulip_botserver": ["py.typed"]},
-)  # type: Dict[str, Any]
-
-setuptools_info = dict(
     install_requires=[
         "zulip",
         "zulip_bots",
         "flask>=0.12.2",
     ],
+    packages=find_packages(exclude=["tests"]),
 )
-
-try:
-    from setuptools import find_packages, setup
-
-    package_info.update(setuptools_info)
-    package_info["packages"] = find_packages(exclude=["tests"])
-
-except ImportError:
-    from distutils.core import setup
-    from distutils.version import LooseVersion
-    from importlib import import_module
-
-    # Manual dependency check
-    def check_dependency_manually(module_name: str, version: Optional[str] = None) -> None:
-        try:
-            module = import_module(module_name)  # type: Any
-            if version is not None:
-                assert LooseVersion(module.__version__) >= LooseVersion(version)
-        except (ImportError, AssertionError):
-            if version is not None:
-                print(
-                    f"{module_name}>={version} is not installed.",
-                    file=sys.stderr,
-                )
-            else:
-                print(f"{module_name} is not installed.", file=sys.stderr)
-            sys.exit(1)
-
-    check_dependency_manually("zulip")
-    check_dependency_manually("zulip_bots")
-    check_dependency_manually("flask", "0.12.2")
-
-    package_info["packages"] = ["zulip_botserver"]
-
-
-setup(**package_info)