Update to_plotly_json docstrings, add to CHANGELOG.md.

Author: itsluketwist

CHANGELOG.md

@@ -2,6 +2,11 @@
 All notable changes to this project will be documented in this file.
 This project adheres to [Semantic Versioning](http://semver.org/).
 
+## UNRELEASED
+
+### Updated
+- Improved json docstrings, added `BasePlotlyType.to_json()` method [[#4301](https://github.com/plotly/plotly.py/pull/4301)]
+
 ## [5.16.1] - 2023-08-16
 
 ### Fixed

packages/python/plotly/plotly/basedatatypes.py

@@ -3318,7 +3318,8 @@ def to_plotly_json(self):
         """
         Convert figure to a JSON representation as a Python dict
 
-        Note: May include some JSON-invalid data types, use the `PlotlyJSONEncoder` util when encoding.
+        Note: May include some JSON-invalid data types, use the `PlotlyJSONEncoder` util
+        or the `to_json` method to encode to a string.
 
         Returns
         -------
@@ -5599,7 +5600,8 @@ def to_plotly_json(self):
         """
         Return plotly JSON representation of object as a Python dict
 
-        Note: May include some JSON-invalid data types, use the `PlotlyJSONEncoder` util when encoding.
+        Note: May include some JSON-invalid data types, use the `PlotlyJSONEncoder` util
+        or the `to_json` method to encode to a string.
 
         Returns
         -------