Updating SDE comparison mode to accept two manifests

[Jorjeous]

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To fix an unused import, you remove the import statement (or, if the symbol is meant to be used, you instead add corresponding code that uses it). Here, the simplest and safest way, without changing functionality, is to delete the import tarfile line.

Concretely, in tools/speech_data_explorer/data_explorer.py, remove line 27 containing import tarfile. No additional methods, imports, or definitions are needed. All other imports and code remain unchanged.

In general, to fix an unused local variable you either remove the variable entirely or rename it to a clearly “unused” name (such as _ or unused_file_type) if it is kept for documentation or unpacking purposes. This preserves code clarity and avoids misleading readers into thinking the value is relevant to the logic.

Here, the right-hand side (parts[0]) has no side effects, so we can safely remove just the file_type assignment without affecting behavior. The best minimal fix is to delete the file_type = parts[0] line, leaving offset, size, and filename unchanged. No additional imports or definitions are needed, and no other parts of parse_dali_index depend on file_type. All edits occur in tools/speech_data_explorer/data_explorer.py within the shown parse_dali_index function.

To fix this while preserving behavior, keep the assignment (so the temp file object stays referenced) but rename the variable to follow the project’s “intentionally unused” naming pattern. That makes it clear that the variable is only there for its side effect (controlling object lifetime) and satisfies CodeQL.

Concretely, in tools/speech_data_explorer/data_explorer.py around line 1311, change _merged_tmp to something like _unused_merged_tmp_ref both in its declaration and where the return from merge_manifests is unpacked. No imports or additional definitions are needed. Functionality is unchanged: the temporary file’s reference is still kept alive; only the variable name changes.