Use the stdlib importlib.metadata when available

The use of importlib_metadata relies on features that were introduced in
python 3.10. Aside for that, it should be fine to use the stdlib
directly.

Fixes pypa#773

setup.cfg

@@ -40,7 +40,7 @@ install_requires=
     requests >= 2.20
     requests-toolbelt >= 0.8.0, != 0.9.0
     urllib3 >= 1.26.0
-    importlib-metadata >= 3.6
+    importlib-metadata >= 3.6; python_version<"3.10"
     keyring >= 15.1
     rfc3986 >= 1.4.0
     rich >= 12.0.0

twine/__init__.py

@@ -29,7 +29,12 @@
 
 __copyright__ = "Copyright 2019 Donald Stufft and individual contributors"
 
-import importlib_metadata
+import sys
+
+if sys.version_info >= (3, 10):
+    import importlib.metadata as importlib_metadata
+else:
+    import importlib_metadata
 
 metadata = importlib_metadata.metadata("twine")
 

twine/cli.py

@@ -13,9 +13,14 @@
 # limitations under the License.
 import argparse
 import logging.config
+import sys
 from typing import Any, List, Tuple
 
-import importlib_metadata
+if sys.version_info >= (3, 10):
+    import importlib.metadata as importlib_metadata
+else:
+    import importlib_metadata
+
 import rich
 import rich.highlighter
 import rich.logging
@@ -70,14 +75,15 @@ def configure_output() -> None:
 
 
 def list_dependencies_and_versions() -> List[Tuple[str, str]]:
-    deps = (
-        "importlib-metadata",
+    deps = [
         "keyring",
         "pkginfo",
         "requests",
         "requests-toolbelt",
         "urllib3",
-    )
+    ]
+    if sys.version_info < (3, 10):
+        deps.append("importlib-metadata")
     return [(dep, importlib_metadata.version(dep)) for dep in deps]
 
 

twine/package.py

@@ -17,9 +17,14 @@
 import os
 import re
 import subprocess
+import sys
 from typing import Dict, NamedTuple, Optional, Sequence, Tuple, Union, cast
 
-import importlib_metadata
+if sys.version_info >= (3, 10):
+    import importlib.metadata as importlib_metadata
+else:
+    import importlib_metadata
+
 import pkginfo
 from rich import print