bpo-38096: Clean up the "struct sequence" / "named tuple" docs (GH-15895) (GH-15961)

diff --git a/Objects/floatobject.c b/Objects/floatobject.c
index 15cbe5c..d909e41 100644
--- a/Objects/floatobject.c
+++ b/Objects/floatobject.c
@@ -43,7 +43,7 @@
 PyDoc_STRVAR(floatinfo__doc__,
 "sys.float_info\n\
 \n\
-A structseq holding information about the float type. It contains low level\n\
+A named tuple holding information about the float type. It contains low level\n\
 information about the precision and internal representation. Please study\n\
 your system's :file:`float.h` for more information.");