Deprecate the import of some development-related names from the global namespace

[jhpalmieri]

Part of #25383

Component: misc

Author: John Palmieri

Branch/Commit: u/jhpalmieri/trac34259-deprecate-some-imports @ 88940c1

Issue created by migration from https://trac.sagemath.org/ticket/34259

[jhpalmieri]

Branch: u/jhpalmieri/trac34259-deprecate-some-imports

[jhpalmieri]

Commit: aa8a0d2

[jhpalmieri]

comment:2

This branch deprecates a bunch of import statements in sage.misc.all. It leaves intact cputime and walltime, but it changes some doctests by explicitly importing them, in case we do eventually want to deprecate them. There are one or two places where cputime was called but not used, and those have been removed. The branch also changes from sage.all import * in sage.tests.benchmark to explicit import statements.

---

New commits:

b20ee44	trac 34259: deprecate some imports from sage.misc.all
aa8a0d2	trac 34259: clarify imports in sage.tests.benchmark

[videlec]

comment:3

The pyflakes report contains a lot of issues, especially related to benchmark.py.

[jhpalmieri]

comment:4

Replying to @videlec:

The pyflakes report contains a lot of issues, especially related to benchmark.py.

Thank you for pointing that out. I can't work on this for a few days, but most of these should be easy to deal with.

[mkoeppe]

comment:5

Regarding cputime and walltime, I think they are in the global namespace for interactive use for timing, like Matlab's tic/toc.

Instead of just deprecating them, I think we should find out what the standard idiom to do this in modern Python is

[jhpalmieri]

comment:6

Instead of cputime and walltime, I have always used %time and %timeit. I'm sure there are other alternatives.

[sagetrac-git]

Changed commit from aa8a0d2 to 88940c1

[sagetrac-git]

Branch pushed to git repo; I updated commit sha1. New commits:

88940c1

trac 34259: fix imports and other pyflakes warnings for tests/benchmark.py

[jhpalmieri]

comment:8

Of course %time and %timeit are for interactive use. Within a program, maybe we could try time.process_time (or process_time_ns), either to rewrite cputime or to replace it. timeit.default_timer could be a replacement for walltime. See https://stackoverflow.com/questions/15176619/timing-the-cpu-time-of-a-python-program in addition to the Python docs. But I think this should be on another ticket.

[jhpalmieri]

comment:9

Anyway, I've fixed most of the pyflakes warnings. The remaining one, src/sage/misc/banner.py:71:9 'sage.all' imported but unused, comes from these lines, and I don't think they need to be changed:

    try:
        import sage.all
        have_sage_all = True
    except ImportError:
        have_sage_all = False

[jhpalmieri]

I revived the branch in the pull request at #35841.

[jhpalmieri]

I think this can be closed: the main issues were addressed in #35841, and whatever's left is not worth keeping.