add metrics warning

arango/database.py

@@ -11,6 +11,8 @@
 from typing import Any, List, Optional, Sequence, Union
 from warnings import warn
 
+from packaging import version
+
 from arango.api import ApiGroup
 from arango.aql import AQL
 from arango.backup import Backup
@@ -838,6 +840,10 @@ def metrics(self) -> Result[str]:
         :return: Server metrics in Prometheus format.
         :rtype: str
         """
+        if version.parse(self.version()) < version.parse("3.10"):
+            m = "You are using the Metrics V2 API with a database version less than 3.10. The old metrics format is not available anymore."  # noqa: E501
+            warn(m, DeprecationWarning, stacklevel=2)
+
         request = Request(method="get", endpoint="/_admin/metrics/v2")
 
         def response_handler(resp: Response) -> str: