skip python<3.9

Author: rmorshea

src/idom/_console/update_html_usages.py

@@ -2,6 +2,7 @@
 
 import ast
 import re
+import sys
 from collections.abc import Sequence
 from dataclasses import dataclass
 from keyword import kwlist
@@ -51,6 +52,8 @@ def update_html_usages(directories: list[str]) -> None:
     just above its changes. As such it requires manual intervention to put those
     comments back in their original location.
     """
+    if sys.version_info < (3, 9):  # pragma: no cover
+        raise RuntimeError("This command requires Python>=3.9")
     for d in directories:
         for file in Path(d).rglob("*.py"):
             result = generate_rewrite(file=file, source=file.read_text())

tests/test__console/test_update_html_usages.py

@@ -1,3 +1,4 @@
+import sys
 from pathlib import Path
 from textwrap import dedent
 
@@ -213,6 +214,7 @@ def func():
     if isinstance(item, str)
     else item,
 )
+@pytest.mark.skipif(sys.version_info < (3, 9), reason="ast.unparse is Python>=3.9")
 def test_generate_rewrite(source, expected):
     actual = generate_rewrite(Path("test.py"), dedent(source).strip())
     if isinstance(expected, str):