Repository: theupdateframework/python-tuf (python)

Issue:
user-agent should maybe mention "python"?
User agent set in tuf/ngclient/_internal/requests_fetcher.py is `tuf/5.0.0` -- this looks good but I think should be `python-tuf/5.0.0` instead as it should identify the complete project when visible in an access log.


Pull request description:
changing user-agent value
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**Description of the changes being introduced by the pull request**:
It's just changing user agent string to `python-tuf/5.0.0` from `tuf/5.0.0`



Fixes #2631 



Patch:
diff --git a/tuf/ngclient/_internal/requests_fetcher.py b/tuf/ngclient/_internal/requests_fetcher.py
index c931b85a..937357a5 100644
--- a/tuf/ngclient/_internal/requests_fetcher.py
+++ b/tuf/ngclient/_internal/requests_fetcher.py
@@ -141,7 +141,7 @@ def _get_session(self, url: str) -> requests.Session:
             session = requests.Session()
             self._sessions[session_index] = session
 
-            ua = f"tuf/{tuf.__version__} {session.headers['User-Agent']}"
+            ua = f"python-tuf/{tuf.__version__} {session.headers['User-Agent']}"
             if self.app_user_agent is not None:
                 ua = f"{self.app_user_agent} {ua}"
             session.headers["User-Agent"] = ua


Test patch:
diff --git a/tests/test_updater_ng.py b/tests/test_updater_ng.py
index ea830c17..73437879 100644
--- a/tests/test_updater_ng.py
+++ b/tests/test_updater_ng.py
@@ -325,7 +325,7 @@ def test_user_agent(self) -> None:
         self.updater.refresh()
         session = next(iter(self.updater._fetcher._sessions.values()))
         ua = session.headers["User-Agent"]
-        self.assertEqual(ua[:4], "tuf/")
+        self.assertEqual(ua[:11], "python-tuf/")
 
         # test custom UA
         updater = Updater(
@@ -339,7 +339,7 @@ def test_user_agent(self) -> None:
         session = next(iter(updater._fetcher._sessions.values()))
         ua = session.headers["User-Agent"]
 
-        self.assertEqual(ua[:16], "MyApp/1.2.3 tuf/")
+        self.assertEqual(ua[:23], "MyApp/1.2.3 python-tuf/")
 
 
 if __name__ == "__main__":