Avoid import outside top-level

[berland]

Keeping as exception at one spot due to circular dependency and one spot due to measurable time-loss to do top-level import.

Ignoring the issue in script/build, this file is being deleted soon.

Issue
Resolves ruff PLC0415

Approach
fix/add exception/comment.

• PR title captures the intent of the changes, and is fitting for release notes.
• Added appropriate release note label
• Commit history is consistent and clean, in line with the contribution guidelines.
• Make sure tests pass locally (after every commit!)

When applicable

• When there are user facing changes: Updated documentation
• New behavior or changes to existing untested code: Ensured that unit tests are added (See Ground Rules).
• Large PR: Prepare changes in small commits for more convenient review
• Bug fix: Add regression test for the bug
• Bug fix: Create Backport PR to latest release

[berland]

import-outside-top-level (PLC0415)

Derived from the Pylint linter.

This rule is in preview and is not stable. The --preview flag is required for use.

What it does

Checks for import statements outside of a module's top-level scope, such
as within a function or class definition.

Why is this bad?

PEP 8 recommends placing imports not only at the top-level of a module,
but at the very top of the file, "just after any module comments and
docstrings, and before module globals and constants."

import statements have effects that are global in scope; defining them at
the top level has a number of benefits. For example, it makes it easier to
identify the dependencies of a module, and ensures that any invalid imports
are caught regardless of whether a specific function is called or class is
instantiated.

An import statement would typically be placed within a function only to
avoid a circular dependency, to defer a costly module load, or to avoid
loading a dependency altogether in a certain runtime environment.

Example

def print_python_version():
    import platform

    print(python.python_version())

Use instead:

import platform


def print_python_version():
    print(python.python_version())

[codecov-commenter]

Codecov Report

Attention: Patch coverage is 50.00000% with 1 line in your changes missing coverage. Please review.

Project coverage is 90.88%. Comparing base (cf02f45) to head (a490506).

Files	Patch %	Lines
src/ert/__main__.py	0.00%	1 Missing ⚠️

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #8295   +/-   ##
=======================================
  Coverage   90.88%   90.88%           
=======================================
  Files         347      347           
  Lines       21076    21076           
=======================================
+ Hits        19154    19155    +1     
+ Misses       1922     1921    -1     

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

[jonathan-eq]

LGTM!

[eivindjahren]

I think I moved these in at some point and it was done for the same reason as

def run_gui_wrapper(args: Namespace, ert_plugin_manager: ErtPluginManager) -> None:
    # Importing ert.gui on-demand saves ~0.5 seconds off `from ert import __main__`
    from ert.gui.main import run_gui  # noqa: PLC0415

When you run ert test_run, gui will not be imported when you place these imports inside getArguments.

[berland]

fixed!