Docstring for `max_delimiter_priority_in_atom()`

diff --git a/black.py b/black.py
index 9f230e794c57f8e45781fa0566495f91a897d812..6dd1e68d184246a886a0d108900000ee5a6d69e1 100644 (file)
--- a/black.py
+++ b/black.py
@@ -2165,6 +2165,11 @@ def is_vararg(leaf: Leaf, within: Set[NodeType]) -> bool:
 
 
 def max_delimiter_priority_in_atom(node: LN) -> int:
+    """Return maximum delimiter priority inside `node`.
+
+    This is specific to atoms with contents contained in a pair of parentheses.
+    If `node` isn't an atom or there are no enclosing parentheses, returns 0.
+    """
     if node.type != syms.atom:
         return 0