Replaced NotImplementedError with NotImplemented

[fazledyn-or]

This PR is made against #5521

🚀 Pull Request

Description

• This PR replaces the usage of NotImplementedError with NotImplemented

More Info

In file: coords.py, class: CellMethod, there is a special method add that raises a NotImplementedError. If a special method supporting a binary operation is not implemented it should return NotImplemented. On the other hand, NotImplementedError should be raised from abstract methods inside user defined base classes to indicate that derived classes should override those methods. iCR suggested that the special method add should return NotImplemented instead of raising an exception.

An example of how NotImplemented helps the interpreter support a binary operation is here.

---

CLA Requirements

This section is only relevant if your project requires contributors to sign a Contributor License Agreement (CLA) for external contributions.

All contributed commits are already automatically signed off.

The meaning of a signoff depends on the project, but it typically certifies that committer has the rights to submit this work under the same license and agrees to a Developer Certificate of Origin (see https://developercertificate.org/ for more information).
- Git Commit SignOff documentation

Sponsorship and Support

This work is done by the security researchers from OpenRefactory and is supported by the Open Source Security Foundation (OpenSSF): Project Alpha-Omega. Alpha-Omega is a project partnering with open source software project maintainers to systematically find new, as-yet-undiscovered vulnerabilities in open source code - and get them fixed – to improve global software supply chain security.

The bug is found by running the Intelligent Code Repair (iCR) tool by OpenRefactory and then manually triaging the results.

---

Consult Iris pull request check list

[codecov]

Codecov Report

Attention: 1 lines in your changes are missing coverage. Please review.

Comparison is base (0b569cd) 89.41% compared to head (e998948) 89.41%.

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #5544   +/-   ##
=======================================
  Coverage   89.41%   89.41%           
=======================================
  Files          89       89           
  Lines       22539    22539           
  Branches     5387     5387           
=======================================
  Hits        20154    20154           
  Misses       1639     1639           
  Partials      746      746           

Files	Coverage Δ
lib/iris/coords.py	93.24% <0.00%> (ø)

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

[trexfeathers]

Thanks for your diligence, @fazledyn-or!

[trexfeathers]

Almost forgot: please could you add a contribution to latest.rst? We love to celebrate contributions from the community.

iris/docs/src/whatsnew/latest.rst

Lines 83 to 103 in b1c91cc

	💼 Internal
	===========
	#. `@trexfeathers`_ and `@ESadek-MO`_ (reviewer) performed a suite of fixes and
	improvements for benchmarking, primarily to get
	:ref:`on demand pull request benchmarking <on_demand_pr_benchmark>`
	working properly. (Main pull request: :pull:`5437`, more detail:
	:pull:`5430`, :pull:`5431`, :pull:`5432`, :pull:`5434`, :pull:`5436`)
	#. `@trexfeathers`_ set a number of memory benchmarks to be on-demand, as they
	were vulnerable to false positives in CI runs. (:pull:`5481`)
	#. `@acchamber`_ and `@ESadek-MO`_ resolved several deprecation to reduce
	number of warnings raised during tests.
	(:pull:`5493`, :pull:`5511`)
	#. `@trexfeathers`_ replaced all uses of the ``logging.WARNING`` level, in
	favour of using Python warnings, following team agreement. (:pull:`5488`)
	#. `@trexfeathers`_ adapted benchmarking to work with ASV ``>=v0.6`` by no
	longer using the ``--strict`` argument. (:pull:`5496`)

[fazledyn-or]

Sorry for the force push. I had committed some unwanted changes. Please look at the latest commit and suggest.

Thanks

[trexfeathers]

Ooops, that failure is because we need your name in this section to get the link to work:

iris/docs/src/whatsnew/latest.rst

Lines 109 to 115 in 561526b

	.. comment
	Whatsnew author names (@github name) in alphabetical order. Note that,
	core dev names are automatically included by the common_links.inc:
	.. _@scottrobinson02: https://github.com/scottrobinson02
	.. _@acchamber: https://github.com/acchamber