Revert psf#6667 to no longer cache a default SSLContext

src/requests/adapters.py

@@ -74,19 +74,6 @@ def SOCKSProxyManager(*args, **kwargs):
 DEFAULT_POOL_TIMEOUT = None
 
 
-try:
-    import ssl  # noqa: F401
-
-    _preloaded_ssl_context = create_urllib3_context()
-    _preloaded_ssl_context.load_verify_locations(
-        extract_zipped_paths(DEFAULT_CA_BUNDLE_PATH)
-    )
-except ImportError:
-    # Bypass default SSLContext creation when Python
-    # interpreter isn't built with the ssl module.
-    _preloaded_ssl_context = None
-
-
 def _urllib3_request_context(
     request: "PreparedRequest",
     verify: "bool | str | None",
@@ -99,19 +86,9 @@ def _urllib3_request_context(
     scheme = parsed_request_url.scheme.lower()
     port = parsed_request_url.port
 
-    # Determine if we have and should use our default SSLContext
-    # to optimize performance on standard requests.
-    poolmanager_kwargs = getattr(poolmanager, "connection_pool_kw", {})
-    has_poolmanager_ssl_context = poolmanager_kwargs.get("ssl_context")
-    should_use_default_ssl_context = (
-        _preloaded_ssl_context is not None and not has_poolmanager_ssl_context
-    )
-
     cert_reqs = "CERT_REQUIRED"
     if verify is False:
         cert_reqs = "CERT_NONE"
-    elif verify is True and should_use_default_ssl_context:
-        pool_kwargs["ssl_context"] = _preloaded_ssl_context
     elif isinstance(verify, str):
         if not os.path.isdir(verify):
             pool_kwargs["ca_certs"] = verify