fix: update documentation to reflect deprecation of from_view() and usage of __datafusion_table_provider__()

Author: kosiew

docs/source/user-guide/io/table_provider.rst

@@ -50,8 +50,10 @@ A complete example can be found in the `examples folder <https://github.com/apac
 Once you have this library available, you can construct a
 :py:class:`~datafusion.TableProvider` in Python and register it with the
 ``SessionContext``.  Table providers can be created either from the PyCapsule exposed by
-your Rust provider or from an existing :py:class:`~datafusion.dataframe.DataFrame`
-using ``TableProvider.from_view()``.
+your Rust provider or from an existing :py:class:`~datafusion.dataframe.DataFrame`.
+Call the provider's ``__datafusion_table_provider__()`` method to obtain the capsule
+before constructing a ``TableProvider``. The ``TableProvider.from_view()`` helper is
+deprecated; instead use ``TableProvider.from_dataframe()`` or ``DataFrame.into_view()``.
 
 .. code-block:: python
 
@@ -60,16 +62,18 @@ using ``TableProvider.from_view()``.
     ctx = SessionContext()
     provider = MyTableProvider()
 
-    capsule_provider = TableProvider.from_capsule(provider)
+    capsule = provider.__datafusion_table_provider__()
+    capsule_provider = TableProvider.from_capsule(capsule)
 
     df = ctx.from_pydict({"a": [1]})
-    view_provider = TableProvider.from_view(df)
+    view_provider = TableProvider.from_dataframe(df)
+    # or: view_provider = df.into_view()
 
     ctx.register_table("capsule_table", capsule_provider)
     ctx.register_table("view_table", view_provider)
 
     ctx.table("capsule_table").show()
     ctx.table("view_table").show()
 
-Both ``TableProvider.from_capsule()`` and ``TableProvider.from_view()`` create
+Both ``TableProvider.from_capsule()`` and ``TableProvider.from_dataframe()`` create
 table providers that can be registered with the SessionContext using ``register_table()``.