Fix Python 3.10 – 3.12+ Compatibility (Hashing and Syntax)

[bharathananth]

Description

This PR addresses several breaking changes and syntax warnings introduced in recent Python versions (3.10, 3.11, and 3.12). These changes ensure that dsc remains functional as older Python versions approach their End-of-Life (EOL).

Key Changes

Hashing Compatibility (Python 3.10+):

String Encoding: Updated all calls to xxh() and hashlib to encode Unicode strings to utf-8 bytes before hashing. This resolves TypeError: Strings must be encoded before hashing.

F-string Syntax: Fixed nested quote errors in dsc_parser.py that caused SyntaxError when using xxh inside list comprehensions.

Regex Refactoring (Python 3.12+):

Raw Strings: Converted strings containing escape sequences (e.g., [, (, {) to raw strings (r'...'). This resolves SyntaxWarning: invalid escape sequence, which is slated to become a hard SyntaxError in future Python releases.

Verification Results

I have verified these changes using the following steps:

[x] Vignette Testing: Successfully ran the official dsc vignettes (including one_sample_location (R scripts) and one_sample_location_python) to completion.

[x] Cache Integrity: Confirmed that the SoS caching mechanism correctly identifies and retrieves task results, proving that the updated hashing logic is consistent.

[x] Multi-Version Test: Verified the fix on Python 3.10, 3.11, and 3.12 environments.

Note on Dependencies

While this PR cleans up all SyntaxWarnings within the dsc source code itself, users may still see warnings originating from the PTable dependency (e.g., SyntaxWarning: "is" with a literal). These are upstream issues in PTable and do not affect the core logic of dsc. I recommend a future update to the dependency pins to a more modern version of prettytable to resolve those remaining notices.