Add warning when running UDFs that Python 3.7 is going away. (#501)

src/tiledb/cloud/__init__.py

@@ -1,5 +1,8 @@
 # This file imports specifically to re-export.
 
+import sys
+import warnings
+
 from . import compute
 from . import dag
 from . import groups
@@ -38,6 +41,15 @@
 from .tasks import task
 from .tiledb_cloud_error import TileDBCloudError
 
+if sys.version_info < (3, 8):
+    warnings.warn(
+        DeprecationWarning(
+            "Python 3.7 has been deprecated and support will soon be fully"
+            " discontinued. Upgrade to Python 3.9 as soon as possible."
+        )
+    )
+
+
 _pickle_compat.patch_cloudpickle()
 _pickle_compat.patch_pandas()
 

src/tiledb/cloud/dag/dag.py

@@ -3,6 +3,7 @@
 import itertools
 import json
 import numbers
+import sys
 import threading
 import time
 import uuid
@@ -608,6 +609,14 @@ def __init__(
         :param deadline: Duration in seconds relative to the workflow start time
             which the workflow is allowed to run before it gets terminated.
         """
+        if sys.version_info < (3, 8):
+            warnings.warn(
+                DeprecationWarning(
+                    "Python 3.7 has been deprecated and support will soon be fully"
+                    " discontinued. Upgrade to Python 3.9 as soon as possible."
+                )
+            )
+
         self.id = uuid.uuid4()
         self.nodes: Dict[uuid.UUID, Node] = {}
         self.nodes_by_name: Dict[str, Node] = {}

src/tiledb/cloud/udf.py

@@ -1,4 +1,5 @@
 import base64
+import sys
 import uuid
 import warnings
 from typing import Any, Callable, Iterable, Optional, Union
@@ -81,6 +82,14 @@ def exec_base(
     :param kwargs: named arguments to pass to function
     """
 
+    if sys.version_info < (3, 8):
+        warnings.warn(
+            DeprecationWarning(
+                "Python 3.7 has been deprecated and support will soon be fully"
+                " discontinued. Upgrade to Python 3.9 as soon as possible."
+            )
+        )
+
     if result_format_version:
         warnings.warn(DeprecationWarning("result_format_version is unused."))