Issue #22004: Correct an argument name.
diff --git a/Doc/library/io.rst b/Doc/library/io.rst
index 7b40085..ab5a043 100644
--- a/Doc/library/io.rst
+++ b/Doc/library/io.rst
@@ -287,7 +287,7 @@
       most *limit* bytes will be read.
 
       The line terminator is always ``b'\n'`` for binary files; for text files,
-      the *newlines* argument to :func:`.open` can be used to select the line
+      the *newline* argument to :func:`.open` can be used to select the line
       terminator(s) recognized.
 
    .. method:: readlines(hint=-1)