Fix the Python lint issues raised by:
% ruff check --select=C4,PERF --ignore=PERF203--statistics | sort -k2

4	C408    	unnecessary-collection-call
1	C416    	unnecessary-comprehension
1	PERF102 	incorrect-dict-iterator
2	PERF401 	manual-list-comprehension
Found 8 errors.
No fixes available (6 hidden fixes can be enabled with the `--unsafe-fixes` option).

Motivation and Context

These proposed changes can make code easier to reason about or faster or both.

% ruff rule PERF401

manual-list-comprehension (PERF401)

Derived from the Perflint linter.

Fix is sometimes available.

What it does

Checks for for loops that can be replaced by a list comprehension.

Why is this bad?

When creating a transformed list from an existing list using a for-loop,
prefer a list comprehension. List comprehensions are more readable and
more performant.

Using the below as an example, the list comprehension is ~10% faster on
Python 3.11, and ~25% faster on Python 3.10.

Note that, as with all perflint rules, this is only intended as a
micro-optimization, and will have a negligible impact on performance in
most cases.

Example

original = list(range(10000))
filtered = []
for i in original:
    if i % 2:
        filtered.append(i)

Use instead:

original = list(range(10000))
filtered = [x for x in original if x % 2]

If you're appending to an existing list, use the extend method instead:

original = list(range(10000))
filtered.extend(x for x in original if x % 2)

Take care that if the original for-loop uses an assignment expression
as a conditional, such as if match:=re.match("\d+","123"), then
the corresponding comprehension must wrap the assignment
expression in parentheses to avoid a syntax error.

How Has This Been Tested?

Breaking Changes

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
• Documentation update

Checklist

• I have read the MCP Documentation
• My code follows the repository's style guidelines
• New and existing tests pass locally
• I have added appropriate error handling
• I have added or updated documentation as needed

Additional context

https://docs.astral.sh/ruff