Update CHANGELOG.md

Co-authored-by: David Hewitt <[email protected]>

CHANGELOG.md

@@ -5,6 +5,10 @@ PyO3 versions, please see the [migration guide](https://pyo3.rs/master/migration
 The format is based on [Keep a Changelog](http://keepachangelog.com/en/1.0.0/)
 and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.html).
 
+## [Unreleased]
+### Removed
+- Remove deprecated ffi definitions `PyUnicode_AsUnicodeCopy`, `PyUnicode_GetMax`, `_Py_CheckRecursionLimit`, `PyObject_AsCharBuffer`, `PyObject_AsReadBuffer`, `PyObject_CheckReadBuffer` and `PyObject_AsWriteBuffer`, which will be removed in Python 3.10. [#1217](https://github.com/PyO3/pyo3/pull/1217)
+
 ## [0.12.2] - 2020-10-12
 ### Added
 - Add support for keyword-only arguments without default values in `#[pyfunction]`. [#1209](https://github.com/PyO3/pyo3/pull/1209)
@@ -15,9 +19,6 @@ and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.
 - Hide docs of PyO3 private implementation details in `pyo3::class::methods`. [#1169](https://github.com/PyO3/pyo3/pull/1169)
 - Fix unnecessary rebuild on PATH changes when the python interpreter is provided by PYO3_PYTHON. [#1231](https://github.com/PyO3/pyo3/pull/1231)
 
-### Removed
-- Removed `PyUnicode_AsUnicodeCopy`, `PyUnicode_GetMax`, `_Py_CheckRecursionLimit`, `PyObject_AsCharBuffer`, `PyObject_AsReadBuffer`, `PyObject_CheckReadBuffer` and `PyObject_AsWriteBuffer` which have been removed in python 3.10
-
 ## [0.12.1] - 2020-09-16
 ### Fixed
 - Fix building for a 32-bit Python on 64-bit Windows with a 64-bit Rust toolchain. [#1179](https://github.com/PyO3/pyo3/pull/1179)