bpo-37979: Add alternative to fromisoformat in documentation (GH-15596)



Adds a link to `dateutil.parser.isoparse` in the documentation.

It would be nice to set up intersphinx for things like this, but I think we can leave that for a separate PR.

CC: @pitrou 

[bpo-37979](https://bugs.python.org/issue37979)


https://bugs.python.org/issue37979



Automerge-Triggered-By: @pitrou
diff --git a/Doc/library/datetime.rst b/Doc/library/datetime.rst
index 0135fa4..50f1b9e 100644
--- a/Doc/library/datetime.rst
+++ b/Doc/library/datetime.rst
@@ -857,7 +857,9 @@
   .. caution::
 
     This does not support parsing arbitrary ISO 8601 strings - it is only intended
-    as the inverse operation of :meth:`datetime.isoformat`.
+    as the inverse operation of :meth:`datetime.isoformat`. A more full-featured
+    ISO 8601 parser, ``dateutil.parser.isoparse`` is available in the third-party package
+    `dateutil <https://dateutil.readthedocs.io/en/stable/parser.html#dateutil.parser.isoparse>`_.
 
   .. versionadded:: 3.7
 
diff --git a/Misc/NEWS.d/next/Documentation/2019-08-29-10-40-05.bpo-37979.TAUx_E.rst b/Misc/NEWS.d/next/Documentation/2019-08-29-10-40-05.bpo-37979.TAUx_E.rst
new file mode 100644
index 0000000..d8d70d6
--- /dev/null
+++ b/Misc/NEWS.d/next/Documentation/2019-08-29-10-40-05.bpo-37979.TAUx_E.rst
@@ -0,0 +1,2 @@
+Added a link to dateutil.parser.isoparse in the datetime.fromisoformat
+documentation. Patch by Paul Ganssle