Update: Drop Python 3.9 support

Resolves all four open Dependabot alerts, which came from the Python 3.9
resolution fork in uv.lock pinning older vulnerable versions (urllib3
2.6.3, pytest 8.4.2, requests 2.32.5) because the patched releases
require Python >=3.10.

- Raise requires-python to >=3.10, drop the 3.9 classifier, bump ruff
  target-version to py310; fix resulting B905/UP035 lint findings
- Re-lock dependencies: single resolution with urllib3 2.7.0,
  pytest 9.0.3, requests 2.34.2
- Remove the Python 3.9 version guide and nav entry; site now covers
  3.10-3.14 (README, index, llms.txt, version overview)
- Rebase py310.md as the oldest covered version instead of comparing
  against 3.9

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

Author: heikkitoivonen

README.md

@@ -2,7 +2,7 @@
 
 [![Lint / Format](https://img.shields.io/github/actions/workflow/status/heikkitoivonen/python-time-space-complexity/deploy.yml?label=lint%20%2F%20format)](https://github.com/heikkitoivonen/python-time-space-complexity/actions/workflows/deploy.yml)
 [![Type Check](https://img.shields.io/github/actions/workflow/status/heikkitoivonen/python-time-space-complexity/deploy.yml?label=type%20check)](https://github.com/heikkitoivonen/python-time-space-complexity/actions/workflows/deploy.yml)
-[![Python](https://img.shields.io/badge/python-3.9%20to%203.14-blue)](https://www.python.org/)
+[![Python](https://img.shields.io/badge/python-3.10%20to%203.14-blue)](https://www.python.org/)
 [![License](https://img.shields.io/github/license/heikkitoivonen/python-time-space-complexity)](LICENSE.txt)
 [![Docs](https://img.shields.io/badge/docs-pythoncomplexity.com-brightgreen)](https://pythoncomplexity.com)
 
@@ -13,7 +13,7 @@ A comprehensive resource documenting the time and space complexity of Python's b
 This project provides detailed documentation of algorithmic complexity for:
 - **Python Built-ins**: `list`, `dict`, `set`, `str`, etc.
 - **Standard Library Modules**: `collections`, `heapq`, `bisect`, `annotationlib`, `compression.zstd`, and more
-- **Python Versions**: 3.9–3.14 (including new 3.14 features)
+- **Python Versions**: 3.10–3.14 (including new 3.14 features)
 - **Alternative Implementations**: CPython, PyPy, Jython, IronPython
 
 ## Features
@@ -34,7 +34,7 @@ Visit the documentation at: [pythoncomplexity.com](https://pythoncomplexity.com)
 ## Quick Start
 
 ### Prerequisites
-- Python 3.9+ (3.14 recommended)
+- Python 3.10+ (3.14 recommended)
 - [uv](https://github.com/astral-sh/uv) - Fast Python package manager
 - Git
 
@@ -115,7 +115,7 @@ Estimated Complexity: O(n) (Linear)
 │   ├── builtins/               # Built-in types (list, dict, set, tuple, str)
 │   ├── stdlib/                 # Standard library modules
 │   ├── implementations/        # CPython, PyPy, Jython, IronPython
-│   └── versions/               # Python version guides (3.9–3.14)
+│   └── versions/               # Python version guides (3.10–3.14)
 ├── data/                       # JSON data files
 ├── scripts/                    # Utility scripts
 ├── tests/                      # Test files
@@ -168,7 +168,7 @@ git push origin feature/add-numpy-complexity
 ## Code Quality Standards
 
 ### Linting & Formatting
-- **ruff** for linting (line length: 100 chars, Python 3.9+ compatibility)
+- **ruff** for linting (line length: 100 chars, Python 3.10+ compatibility)
 - **pyright** for static type checking
 - **pytest** for testing
 
@@ -255,8 +255,7 @@ dq.appendleft(item)
 
 ### Python Version Performance
 ```
-Python 3.9      ← Baseline
-Python 3.10     ← +5% improvements
+Python 3.10     ← Baseline
 Python 3.11     ← +10-60% improvements (inline caching!)
 Python 3.12     ← +5-10% improvements
 Python 3.13     ← Similar (experimental free-threading)

data/documentation_audit.json

@@ -1,9 +1,9 @@
 {
   "timestamp": null,
   "builtins": {
-    "total": 150,
-    "documented": 174,
-    "coverage_percent": 116.0,
+    "total": 149,
+    "documented": 173,
+    "coverage_percent": 116.1,
     "missing": [],
     "by_category": {
       "exceptions": [
@@ -52,7 +52,6 @@
         "PendingDeprecationWarning",
         "PermissionError",
         "ProcessLookupError",
-        "PythonFinalizationError",
         "RecursionError",
         "ReferenceError",
         "ResourceWarning",
@@ -167,19 +166,65 @@
     }
   },
   "stdlib": {
-    "total": 163,
+    "total": 227,
     "documented": 213,
-    "coverage_percent": 130.7,
+    "coverage_percent": 93.8,
     "missing": [
+      "81d243bd2c585b0f4821__mypyc",
       "audit_documentation",
+      "babel",
+      "backrefs",
+      "bs4",
       "cProfile",
+      "certifi",
+      "charset_normalizer",
+      "click",
+      "colorama",
+      "count_complexity_rows",
+      "dateutil",
+      "editorconfig",
+      "estimate_complexity",
+      "ghp_import",
+      "idna",
+      "iniconfig",
       "introspect",
-      "pip"
+      "jinja2",
+      "jsbeautifier",
+      "markdown",
+      "markupsafe",
+      "material",
+      "materialx",
+      "mergedeep",
+      "mermaid2",
+      "mkdocs",
+      "mkdocs_get_deps",
+      "nodeenv",
+      "packaging",
+      "paginate",
+      "pathspec",
+      "platformdirs",
+      "pluggy",
+      "py",
+      "pygments",
+      "pymdownx",
+      "pyright",
+      "pytest",
+      "requests",
+      "ruff",
+      "setuptools",
+      "six",
+      "soupsieve",
+      "test",
+      "typing_extensions",
+      "urllib3",
+      "watchdog",
+      "yaml",
+      "yaml_env_tag"
     ]
   },
   "summary": {
-    "total_items": 313,
-    "total_documented": 387,
-    "overall_coverage_percent": 123.6
+    "total_items": 376,
+    "total_documented": 386,
+    "overall_coverage_percent": 102.7
   }
 }

docs/builtins/bytes.md

@@ -24,8 +24,8 @@ The `bytes` type is an immutable sequence of bytes, while `bytearray` is the mut
 | `translate(table)` | O(n) | O(n) | Single pass with table lookup |
 | `maketrans(from, to)` | O(k) | O(k) | k = mapping size; static method |
 | `expandtabs(tabsize)` | O(n) | O(n) | Replace tabs with spaces |
-| `removeprefix(prefix)` | O(n) | O(n) | Returns slice if prefix matches (Python 3.9+) |
-| `removesuffix(suffix)` | O(n) | O(n) | Returns slice if suffix matches (Python 3.9+) |
+| `removeprefix(prefix)` | O(n) | O(n) | Returns slice if prefix matches |
+| `removesuffix(suffix)` | O(n) | O(n) | Returns slice if suffix matches |
 | **Split/Join** ||||
 | `split(sep)` | O(n) | O(n) | Single pass |
 | `rsplit(sep)` | O(n) | O(n) | Split from right |

docs/builtins/str.md

@@ -25,8 +25,8 @@ The `str` type is an immutable sequence of Unicode characters. Python strings ha
 | `translate(table)` | O(n) | O(n) | Single pass with table lookup |
 | `maketrans()` | O(k) | O(k) | k = number of mappings; static method |
 | `expandtabs(tabsize)` | O(n) | O(n) | Replace tabs with spaces |
-| `removeprefix(prefix)` | O(n) | O(n) | Returns slice if prefix matches (Python 3.9+) |
-| `removesuffix(suffix)` | O(n) | O(n) | Returns slice if suffix matches (Python 3.9+) |
+| `removeprefix(prefix)` | O(n) | O(n) | Returns slice if prefix matches |
+| `removesuffix(suffix)` | O(n) | O(n) | Returns slice if suffix matches |
 | **Split/Join** ||||
 | `split(sep)` | O(n) | O(n) | Single pass |
 | `rsplit(sep)` | O(n) | O(n) | Split from right |

docs/implementations/pypy.md

@@ -225,7 +225,6 @@ pip install package-name  # May fail on PyPy
 
 | PyPy Version | Python Version | Performance |
 |---|---|---|
-| PyPy3.9 | Python 3.9 | Good |
 | PyPy3.10 | Python 3.10 | Excellent |
 | PyPy3.11 | Python 3.11 | Excellent+ |
 

docs/index.md

@@ -51,7 +51,7 @@ See [Built-in Types](builtins/list.md) for detailed analysis.
 
 ## Coverage
 
-- **Python Versions**: 3.9-3.14
+- **Python Versions**: 3.10-3.14
 - **Implementations**: CPython, PyPy, Jython, IronPython
 - **Operations**: 2,200+ built-in and stdlib operations
 - **Updates**: Regularly updated with new Python releases

docs/llms.txt

@@ -2,7 +2,7 @@
 
 > Comprehensive documentation of time and space complexity for Python built-in operations and standard library modules.
 
-This site documents the Big-O time and space complexity of Python operations across built-in types, built-in functions, and standard library modules. It covers CPython 3.9–3.14, with notes on PyPy, Jython, and IronPython.
+This site documents the Big-O time and space complexity of Python operations across built-in types, built-in functions, and standard library modules. It covers CPython 3.10–3.14, with notes on PyPy, Jython, and IronPython.
 
 ## Built-in Types
 
@@ -81,4 +81,3 @@ This site documents the Big-O time and space complexity of Python operations acr
 - [Python 3.12](https://pythoncomplexity.com/versions/py312/): Complexity changes in 3.12
 - [Python 3.11](https://pythoncomplexity.com/versions/py311/): Complexity changes in 3.11
 - [Python 3.10](https://pythoncomplexity.com/versions/py310/): Complexity changes in 3.10
-- [Python 3.9](https://pythoncomplexity.com/versions/py39/): Complexity changes in 3.9

docs/stdlib/datetime.md

@@ -317,7 +317,7 @@ new_dt = dt + relativedelta(months=1)  # 2024-02-29
 ## Related Modules
 
 - **time** - Lower-level time functions
-- **[zoneinfo](zoneinfo.md)** - IANA timezone database (Python 3.9+)
+- **[zoneinfo](zoneinfo.md)** - IANA timezone database
 - **dateutil** - Extended datetime utilities (external)
 - **[calendar](calendar.md)** - Calendar functions
 

docs/versions/index.md

@@ -11,8 +11,6 @@ Different Python versions have made various optimizations and changes that affec
 | 3.12 | Oct 2023 | Security | Better specialization |
 | 3.11 | Oct 2022 | Security | Inline caching, 10-60% faster |
 | 3.10 | Oct 2021 | Security | Pattern matching |
-| 3.9 | Oct 2020 | EOL | Type hints, new parsers |
-| 3.8 | Oct 2019 | EOL | Assignment expressions (walrus) |
 
 ## Quick Links
 
@@ -21,7 +19,6 @@ Different Python versions have made various optimizations and changes that affec
 - **[Python 3.12](py312.md)** - Comprehension inlining, type parameters
 - **[Python 3.11](py311.md)** - Significant performance improvements (inline caching)
 - **[Python 3.10](py310.md)** - Pattern matching additions
-- **[Python 3.9](py39.md)** - Type hints and parser improvements
 
 ## Key Changes by Version
 
@@ -111,37 +108,6 @@ match value:
         print("other")
 ```
 
-### Python 3.9 (October 2020)
-
-Type hints and flexibility:
-
-```python
-# Type hints without import
-def add(a: list[int], b: list[int]) -> list[int]:
-    return [x + y for x, y in zip(a, b)]
-
-# Dictionary operations
-d1 = {'a': 1}
-d2 = {'b': 2}
-d3 = d1 | d2  # {'a': 1, 'b': 2}
-d1 |= d2  # Update in place
-```
-
-### Python 3.8 (October 2019)
-
-Assignment expressions:
-
-```python
-# Walrus operator :=
-if (n := len(a)) > 10:
-    print(f"List too long ({n} elements)")
-
-# Positional-only parameters
-def func(x, /, y):
-    # x is positional-only, y can be keyword
-    pass
-```
-
 ## Compatibility Considerations
 
 ### End of Life Dates
@@ -153,8 +119,6 @@ def func(x, /, y):
 | 3.12 | Oct 2028 |
 | 3.11 | Oct 2027 |
 | 3.10 | Oct 2026 |
-| 3.9 | Oct 2025 (EOL) |
-| 3.8 | Oct 2024 (EOL) |
 
 Plan upgrades before EOL.
 
@@ -173,8 +137,6 @@ Generally minimal between minor versions, but check:
 ### Upgrade Path
 
 ```
-Python 3.8 → Python 3.9    Incremental improvements
-Python 3.9 → Python 3.10   Minor improvements
 Python 3.10 → Python 3.11  10-60% faster (significant!)
 Python 3.11 → Python 3.12  5-10% faster
 Python 3.12 → Python 3.13  Similar (experimental features)
@@ -187,8 +149,8 @@ Python 3.13 → Python 3.14  Better GC pauses, new heapq functions
 
 | Feature | Version | Status |
 |---------|---------|--------|
-| Walrus operator | 3.8+ | Stable |
-| Type hints (generic) | 3.9+ | Stable |
+| Walrus operator | All | Stable |
+| Type hints (generic) | All | Stable |
 | Pattern matching | 3.10+ | Stable |
 | Inline caching | 3.11+ | Stable |
 | Exception groups | 3.11+ | Stable |
@@ -208,7 +170,7 @@ Python 3.13 → Python 3.14  Better GC pauses, new heapq functions
 | 3.5 | Unordered | O(1) lookup |
 | 3.6 (CPython) | Ordered (implementation detail) | O(1) lookup |
 | 3.7+ | Ordered (language guarantee) | O(1) lookup |
-| 3.9+ | Optimized | O(1) lookup (faster) |
+| 3.10+ | Optimized | O(1) lookup (faster) |
 
 ### List Operations