revert: pluggable auth support #995

google/auth/_default.py

@@ -324,23 +324,14 @@ def _get_external_account_credentials(
         google.auth.exceptions.DefaultCredentialsError: if the info dictionary
             is in the wrong format or is missing required information.
     """
-    # There are currently 3 types of external_account credentials.
+    # There are currently 2 types of external_account credentials.
     if info.get("subject_token_type") == _AWS_SUBJECT_TOKEN_TYPE:
         # Check if configuration corresponds to an AWS credentials.
         from google.auth import aws
 
         credentials = aws.Credentials.from_info(
             info, scopes=scopes, default_scopes=default_scopes
         )
-    elif (
-        info.get("credential_source") is not None
-        and info.get("credential_source").get("executable") is not None
-    ):
-        from google.auth import pluggable
-
-        credentials = pluggable.Credentials.from_info(
-            info, scopes=scopes, default_scopes=default_scopes
-        )
     else:
         try:
             # Check if configuration corresponds to an Identity Pool credentials.