Use modern Python syntax features

twine/__main__.py

@@ -27,10 +27,7 @@ def main():
     try:
         return dispatch(sys.argv[1:])
     except (exceptions.TwineException, requests.exceptions.HTTPError) as exc:
-        return '{0}: {1}'.format(
-            exc.__class__.__name__,
-            exc.args[0],
-        )
+        return '{}: {}'.format(exc.__class__.__name__, exc.args[0])
 
 
 if __name__ == "__main__":

twine/cli.py

@@ -29,7 +29,7 @@
 
 def _registered_commands(group='twine.registered_commands'):
     registered_commands = pkg_resources.iter_entry_points(group=group)
-    return dict((c.name, c) for c in registered_commands)
+    return {c.name: c for c in registered_commands}
 
 
 def list_dependencies_and_versions():
@@ -44,7 +44,7 @@ def list_dependencies_and_versions():
 
 def dep_versions():
     return ', '.join(
-        '{0}: {1}'.format(*dependency)
+        '{}: {}'.format(*dependency)
         for dependency in list_dependencies_and_versions()
     )
 
@@ -55,8 +55,10 @@ def dispatch(argv):
     parser.add_argument(
         "--version",
         action="version",
-        version="%(prog)s version {0} ({1})".format(twine.__version__,
-                                                    dep_versions()),
+        version="%(prog)s version {} ({})".format(
+            twine.__version__,
+            dep_versions(),
+        ),
     )
     parser.add_argument(
         "command",

twine/commands/register.py

@@ -24,12 +24,12 @@
 def register(register_settings, package):
     repository_url = register_settings.repository_config['repository']
 
-    print("Registering package to {0}".format(repository_url))
+    print("Registering package to {}".format(repository_url))
     repository = register_settings.create_repository()
 
     if not os.path.exists(package):
         raise exceptions.PackageNotFound(
-            '"{0}" does not exist on the file system.'.format(package)
+            '"{}" does not exist on the file system.'.format(package)
         )
 
     resp = repository.register(

twine/commands/upload.py

@@ -28,7 +28,7 @@ def skip_upload(response, skip_existing, package):
     filename = package.basefilename
     msg_400 = (
         # Old PyPI message:
-        'A file named "{0}" already exists for'.format(filename),
+        'A file named "{}" already exists for'.format(filename),
         # Warehouse message:
         'File already exists',
         # Nexus Repository OSS message:
@@ -55,21 +55,19 @@ def upload(upload_settings, dists):
     dists = _find_dists(dists)
 
     # Determine if the user has passed in pre-signed distributions
-    signatures = dict(
-        (os.path.basename(d), d) for d in dists if d.endswith(".asc")
-    )
+    signatures = {os.path.basename(d): d for d in dists if d.endswith(".asc")}
     uploads = [i for i in dists if not i.endswith(".asc")]
     upload_settings.check_repository_url()
     repository_url = upload_settings.repository_config['repository']
 
-    print("Uploading distributions to {0}".format(repository_url))
+    print("Uploading distributions to {}".format(repository_url))
 
     repository = upload_settings.create_repository()
 
     for filename in uploads:
         package = PackageFile.from_filename(filename, upload_settings.comment)
         skip_message = (
-            "  Skipping {0} because it appears to already exist".format(
+            "  Skipping {} because it appears to already exist".format(
                 package.basefilename)
         )
 

twine/exceptions.py

@@ -50,10 +50,10 @@ class UploadToDeprecatedPyPIDetected(TwineException):
     @classmethod
     def from_args(cls, target_url, default_url, test_url):
         """Return an UploadToDeprecatedPyPIDetected instance."""
-        return cls("You're trying to upload to the legacy PyPI site '{0}'. "
+        return cls("You're trying to upload to the legacy PyPI site '{}'. "
                    "Uploading to those sites is deprecated. \n "
                    "The new sites are pypi.org and test.pypi.org. Try using "
-                   "{1} (or {2}) to upload your packages instead. "
+                   "{} (or {}) to upload your packages instead. "
                    "These are the default URLs for Twine now. \n More at "
                    "https://packaging.python.org/guides/migrating-to-pypi-org/"
                    " .".format(target_url, default_url, test_url)

twine/package.py

@@ -160,7 +160,7 @@ def add_gpg_signature(self, signature_filepath, signature_filename):
             self.gpg_signature = (signature_filename, gpg.read())
 
     def sign(self, sign_with, identity):
-        print("Signing {0}".format(self.basefilename))
+        print("Signing {}".format(self.basefilename))
         gpg_args = (sign_with, "--detach-sign")
         if identity:
             gpg_args += ("--local-user", identity)

twine/repository.py

@@ -28,7 +28,7 @@
 
 import twine
 
-KEYWORDS_TO_NOT_FLATTEN = set(["gpg_signature", "content"])
+KEYWORDS_TO_NOT_FLATTEN = {"gpg_signature", "content"}
 
 LEGACY_PYPI = 'https://pypi.python.org/'
 LEGACY_TEST_PYPI = 'https://testpypi.python.org/'
@@ -106,7 +106,7 @@ def register(self, package):
             "protocol_version": "1",
         })
 
-        print("Registering {0}".format(package.basefilename))
+        print("Registering {}".format(package.basefilename))
 
         data_to_send = self._convert_data_to_list_of_tuples(data)
         encoder = MultipartEncoder(data_to_send)
@@ -130,7 +130,7 @@ def _upload(self, package):
 
         data_to_send = self._convert_data_to_list_of_tuples(data)
 
-        print("Uploading {0}".format(package.basefilename))
+        print("Uploading {}".format(package.basefilename))
 
         with open(package.filename, "rb") as fp:
             data_to_send.append((

twine/utils.py

@@ -115,7 +115,7 @@ def get_repository_from_config(config_file, repository, repository_url=None):
         }
     if repository_url and "://" not in repository_url:
         raise exceptions.UnreachableRepositoryURLDetected(
-            "Repository URL {0} has no protocol. Please add "
+            "Repository URL {} has no protocol. Please add "
             "'https://'. \n".format(repository_url))
     try:
         return get_config(config_file)[repository]
@@ -133,8 +133,8 @@ def get_repository_from_config(config_file, repository, repository_url=None):
         raise exceptions.InvalidConfiguration(msg)
 
 
-_HOSTNAMES = set(["pypi.python.org", "testpypi.python.org", "upload.pypi.org",
-                  "test.pypi.org"])
+_HOSTNAMES = {"pypi.python.org", "testpypi.python.org", "upload.pypi.org",
+              "test.pypi.org"}
 
 
 def normalize_repository_url(url):