Use underscore for new API

src/humanize/__init__.py

@@ -4,7 +4,7 @@
 
 from humanize.filesize import naturalsize
 from humanize.i18n import activate, deactivate, decimal_separator, thousands_separator
-from humanize.lists import naturallist
+from humanize.lists import natural_list
 from humanize.number import (
     apnumber,
     clamp,
@@ -39,7 +39,7 @@
     "naturaldate",
     "naturalday",
     "naturaldelta",
-    "naturallist",
+    "natural_list",
     "naturalsize",
     "naturaltime",
     "ordinal",

src/humanize/lists.py

@@ -4,20 +4,20 @@
 
 from typing import Any
 
-__all__ = ["naturallist"]
+__all__ = ["natural_list"]
 
 
-def naturallist(items: list[Any]) -> str:
+def natural_list(items: list[Any]) -> str:
     """Natural list.
 
     Convert a list of items into a human-readable string with commas and 'and'.
 
     Examples:
-        >>> naturallist(["one", "two", "three"])
+        >>> natural_list(["one", "two", "three"])
         'one, two and three'
-        >>> naturallist(["one", "two"])
+        >>> natural_list(["one", "two"])
         'one and two'
-        >>> naturallist(["one"])
+        >>> natural_list(["one"])
         'one'
 
     Args:

tests/test_lists.py

@@ -17,7 +17,7 @@
         ([[1, "two"]], "1 and two"),
     ],
 )
-def test_naturallist(
+def test_natural_list(
     test_args: list[str] | list[int] | list[str | int], expected: str
 ) -> None:
-    assert humanize.naturallist(*test_args) == expected
+    assert humanize.natural_list(*test_args) == expected