Python Docstring Writer (reST)

Write consistent, high-signal docstrings using reST roles for cross-linking. Optimize for: fast scanning in IDE/tooltips, friendly references, minimal redundancy with type hints, and explaining why/behavior rather than restating types.

Conventions: Type aliases/constants → immediate string literal. Classes/functions → PEP 257 docstring. Attributes/TypedDict keys → trailing docstring. Cross-references → reST roles (e.g. :class:`Foo, :meth:`Bar.baz), not plain text. For @overload and :class:typing.Protocol, follow the dedicated sections below.

1. Type aliases / constants

Docstring immediately after the assignment. One line when possible. Use double backticks for literals (e.g. "dict", None). Prefer meaning and effects over restating the type.

RowFactory = Literal["tuple", "dict"]
"""Row format for fetch methods: ``"tuple"`` for sequences, ``"dict"`` for column-keyed dicts."""

IsolationLevel = Literal["repeatable read", "serializable"]
"""Supported transaction isolation levels."""