Bug: Remove use of assert for pydantic import flow control

[peterschutt]

Description

It was a poor choice to use assertions for the Pydantic import version discrimination refactor in #3347, as they can be optimized away.

We should revert to raising some other exception type where this was applied.

litestar/litestar/contrib/pydantic/pydantic_dto_factory.py

Lines 26 to 37 in fe73848

	try:
	import pydantic as pydantic_v2
	assert pydantic_v2.__version__.startswith("2.") # noqa: S101
	from pydantic import ValidationError as ValidationErrorV2
	from pydantic import v1 as pydantic_v1
	from pydantic.v1 import ValidationError as ValidationErrorV1
	ModelType: TypeAlias = "pydantic_v1.BaseModel | pydantic_v2.BaseModel"
	except AssertionError:

URL to code causing the issue

No response

MCVE

# Your MCVE code here

Steps to reproduce

1. Go to '...'
2. Click on '....'
3. Scroll down to '....'
4. See error

Screenshots

"![SCREENSHOT_DESCRIPTION](SCREENSHOT_LINK.png)"

Logs

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Litestar Version

v2.8.2

Platform

• Linux
• Mac
• Windows
• Other (Please specify in the description above)

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[provinzkraut]

Why not just raise an ImportError?

[peterschutt]

Why not just raise an ImportError?

Yeah

[github-actions]

This issue has been closed in #3359. The change will be included in the upcoming patch release.

[github-actions]

A fix for this issue has been released in v2.8.3