[Checkins] [zopefoundation/zope.interface] 61c6d5: Make the singleton _empty immutable.

[Jason Madden]

  Branch: refs/heads/master
  Home:   https://github.com/zopefoundation/zope.interface
  Commit: 61c6d54ebad0cce407169a27f7a199fc80fdc03a
      https://github.com/zopefoundation/zope.interface/commit/61c6d54ebad0cce407169a27f7a199fc80fdc03a
  Author: Jason Madden <jamadden at gmail.com>
  Date:   2020-01-27 (Mon, 27 Jan 2020)

  Changed paths:
    M CHANGES.rst
    M src/zope/interface/declarations.py
    M src/zope/interface/tests/test_declarations.py

  Log Message:
  -----------
  Make the singleton _empty immutable.

Fixes #158


  Commit: 7a9924b85a1ddcc54cfd3c5d47f51f358dbeda0b
      https://github.com/zopefoundation/zope.interface/commit/7a9924b85a1ddcc54cfd3c5d47f51f358dbeda0b
  Author: Jason Madden <jamadden at gmail.com>
  Date:   2020-01-27 (Mon, 27 Jan 2020)

  Changed paths:
    M src/zope/interface/declarations.py

  Log Message:
  -----------
  Add comment detailing why __bases__ can be set per review.


  Commit: 49126928256538029ed8ae51c38cc945d726fd7d
      https://github.com/zopefoundation/zope.interface/commit/49126928256538029ed8ae51c38cc945d726fd7d
  Author: Jason Madden <jamadden at gmail.com>
  Date:   2020-01-27 (Mon, 27 Jan 2020)

  Changed paths:
    M CHANGES.rst
    M src/zope/interface/declarations.py
    M src/zope/interface/tests/test_declarations.py

  Log Message:
  -----------
  Merge pull request #160 from zopefoundation/issue158

Make the singleton _empty immutable.


Compare: https://github.com/zopefoundation/zope.interface/compare/c120080902ea...491269282565