e Drop CI support for 2.7
e Drop CI support for 2.7

The library now uses 3.5+-specific code

Co-Authored-By: Tim Preece <40b5840c2c710d516b06284d4efee17b7a975c19@users.noreply.github.com>
Co-Authored-By: Clare Macrae <64b2b6d12bfe4baae7dad3d018f8cbf6b0e7a044@cfmacrae.fastmail.co.uk>

approvals/ApprovalTests.Python,tdpreece/ApprovalTests.Python,approvals/ApprovalTests.Python,approvals/ApprovalTests.Python