Cleanup old "old_plugins" import code

[RayBB]

Problem

@cdrini mentioned here that this code is very challenging to read and a bit too magical we should simplify it if we can, especially as we have to keep digging deeper into web.py for the fastapi migration.

openlibrary/openlibrary/code.py

Lines 16 to 45 in 7ac77b5

	old_plugins = [
	"openlibrary",
	"worksearch",
	"inside",
	"books",
	"admin",
	"upstream",
	"importapi",
	]
	def setup():
	setup_logging()
	logger = logging.getLogger("openlibrary")
	logger.info("Application init")
	for p in old_plugins:
	logger.info("loading plugin %s", p)
	modname = f"openlibrary.plugins.{p}.code"
	path = "openlibrary/plugins/" + p
	template.load_templates(path, lazy=True)
	macro.load_macros(path, lazy=True)
	i18n.load_strings(path)
	__import__(modname, globals(), locals(), ['plugins'])
	delegate.plugins += [
	delegate._make_plugin_module('openlibrary.plugins.' + name)
	for name in old_plugins
	]

Reproducing the bug

It's not a bug...

Context

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Breakdown

Requirements Checklist

• [ ]

Related files

Stakeholders

• @cdrini

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