Doc: Add a link to tutorial page from `open()` doc (GH-21737)

Adds a link to the "Reading and Writing Files" page so users can
more easily discover how file handles are handled with the `with`
context manager vs without it.
(cherry picked from commit 705f14556545699ab615ec98f707b438f9603767)

Co-authored-by: Benjamin Kane <bbkane@users.noreply.github.com>

diff --git a/Doc/library/functions.rst b/Doc/library/functions.rst
index e9c92f7c8210d16135ccd72353182786358c70ea..d0f607296e86c8dce30e386ab4ae6773c4dd7751 100644 (file)
--- a/Doc/library/functions.rst
+++ b/Doc/library/functions.rst
@@ -1041,7 +1041,8 @@ are always available.  They are listed here in alphabetical order.
 .. function:: open(file, mode='r', buffering=-1, encoding=None, errors=None, newline=None, closefd=True, opener=None)
 
    Open *file* and return a corresponding :term:`file object`.  If the file
-   cannot be opened, an :exc:`OSError` is raised.
+   cannot be opened, an :exc:`OSError` is raised. See
+   :ref:`tut-files` for more examples of how to use this function.
 
    *file* is a :term:`path-like object` giving the pathname (absolute or
    relative to the current working directory) of the file to be opened or an