Use [] and {} instead of list() and dict()

[benediktjohannes]

Description

See also #8747

Types of changes

• Non-breaking change (fix or new feature that would not break existing functionality).
• Breaking change (fix or new feature that would cause existing functionality to change).
• New tests added to cover the changes.
• Integration tests passed locally by running ./runtests.sh -f -u --net --coverage.
• Quick tests passed locally by running ./runtests.sh --quick --unittests --disttests.
• In-line docstrings updated.
• Documentation updated, tested make html command in the docs/ folder.

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

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📝 Walkthrough

Walkthrough

Modified monai/transforms/inverse.py to replace two defaultdict-like initializations with literal equivalents. In the track_transform_meta function, changed dict() to {} and list() to [] when accessing nested transform-trace status structures. The behavior remains unchanged; only syntax preference was updated.

Estimated code review effort

🎯 1 (Trivial) | ⏱️ ~2 minutes

🚥 Pre-merge checks | ✅ 2 | ❌ 1

❌ Failed checks (1 inconclusive)

Check name	Status	Explanation	Resolution
Description check	❓ Inconclusive	Description references issue #8747 and indicates it's a non-breaking change, but lacks a detailed explanation of what was changed and why.	Add a brief description of the specific changes made (which file, which lines, what was replaced) and the rationale for the change.

✅ Passed checks (2 passed)

Check name	Status	Explanation
Title check	✅ Passed	Title directly summarizes the main change: replacing list() and dict() calls with literal [] and {} syntax.
Docstring Coverage	✅ Passed	Docstring coverage is 100.00% which is sufficient. The required threshold is 80.00%.

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✨ Finishing Touches

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• 📝 Generate docstrings (commit on current branch)

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Post copyable unit tests in a comment

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[benediktjohannes]

@coderabbitai do you agree with these changes?

[coderabbitai]

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🧩 Analysis chain

🏁 Script executed:

#!/bin/bash
# Get the diff for the PR
git diff origin/dev...HEAD -- monai/transforms/inverse.py

Length of output: 792

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🏁 Script executed:

#!/bin/bash
# Get more context around the changed lines
cat monai/transforms/inverse.py | grep -n -B 5 -A 5 "get(TraceKeys.STATUSES"

Length of output: 551

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🏁 Script executed:

#!/bin/bash
# Check if there are any other occurrences of dict() or list() in the same file
rg -n '\b(dict|list)\(\)' monai/transforms/inverse.py

Length of output: 0

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@benediktjohannes Yes, I agree with these changes. Using [] and {} instead of list() and dict() is:

1. More Pythonic - follows PEP 8 style guidelines
2. Slightly faster - literal syntax avoids name lookups
3. More concise - improves readability

The changes are functionally equivalent and safe in this context (default arguments to .get() methods). The PR correctly identified and updated all instances in the file.

[benediktjohannes]

Wow! I am amazed how cool this tool is, I thought that this would definitely not work, just to chat here with the AI, very nice and helpful for workflows! Appreciate it! 👍

[ericspod]

Hi @benediktjohannes I commented in another PR about replacing names like this with literal syntax. I suppose this saves a name lookup but I wonder if the interpreter doesn't replace these things automatically anyway. Do you actually see any speedup here? There's probably many other places in MONAI that should have this done as well.