Fix documentation for input and output tutorial (GH-8231)

The ValueError message ends with a period.
(cherry picked from commit 9cffdbffc3b2dec18def1c3e8cfa166d01d609df)

Co-authored-by: Lysandros Nikolaou <lisandrosnik@gmail.com>

diff --git a/Doc/tutorial/inputoutput.rst b/Doc/tutorial/inputoutput.rst
index d5531029d064c2de66486b5a0db692f2fe18545b..9fd939a20388ac8b322b4a64ff1c05b1d5cc380e 100644 (file)
--- a/Doc/tutorial/inputoutput.rst
+++ b/Doc/tutorial/inputoutput.rst
@@ -289,7 +289,7 @@ automatically fail. ::
    >>> f.read()
    Traceback (most recent call last):
      File "<stdin>", line 1, in <module>
-   ValueError: I/O operation on closed file
+   ValueError: I/O operation on closed file.
 
 
 .. _tut-filemethods: