utils: ensure Downloader defaults to Authenticator

src/poetry/utils/helpers.py

@@ -20,10 +20,9 @@
 from typing import Any
 from typing import overload
 
-import requests
-
 from requests.utils import atomic_open
 
+from poetry.utils.authenticator import Authenticator
 from poetry.utils.constants import REQUESTS_TIMEOUT
 
 
@@ -35,8 +34,6 @@
     from poetry.core.packages.package import Package
     from requests import Session
 
-    from poetry.utils.authenticator import Authenticator
-
 logger = logging.getLogger(__name__)
 prioritised_hash_types: tuple[str, ...] = tuple(
     t
@@ -171,10 +168,10 @@ def __init__(
     ):
         self._dest = dest
 
-        get = requests.get if not session else session.get
+        session = session or Authenticator()
         headers = {"Accept-Encoding": "Identity"}
 
-        self._response = get(
+        self._response = session.get(
             url, stream=True, headers=headers, timeout=REQUESTS_TIMEOUT
         )
         self._response.raise_for_status()