We have agreed that instead of having multiple individual functions that allow one to change or inspect from the return output the (previous or current) value of a certain global setting, there should be a single function that will enable the getting & setting of all such variables. (The existing individual functions can then be deprecated after a sufficient amount of time such that this would be an eventual API change.)

The existing functions that would be consolidated as such are those with capitalised names listed as 'cf functions' in the documentation, e.g. cf.:

• ATOL & RTOL;
• SET_PERFORMANCE;
• RELAXED_IDENTITIES.

and should include, as a new global setting, the lowest-severity logging level when logging is implemented (see #37).

It should still be workable on a single-setting basis, which is simple enough as users can specify the setting & desired value by keyword argument, & an obvious return structure would be a dictionary such that they can use indexing as standard to pick out the item they are interested in.