Merge 9adea0af2e into e3bd7721c8

* [pre-commit.ci] pre-commit autoupdate

updates:
- [github.com/astral-sh/ruff-pre-commit: v0.7.2 → v0.7.3](https://github.com/astral-sh/ruff-pre-commit/compare/v0.7.2...v0.7.3)
- [github.com/abravalheri/validate-pyproject: v0.22 → v0.23](https://github.com/abravalheri/validate-pyproject/compare/v0.22...v0.23)

* Update sudoku_solver.py

---------

Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>
Co-authored-by: Christian Clauss <cclauss@me.com>

.pre-commit-config.yaml

@@ -16,7 +16,7 @@ repos:
       - id: auto-walrus
 
   - repo: https://github.com/astral-sh/ruff-pre-commit
-    rev: v0.7.1
+    rev: v0.7.3
     hooks:
       - id: ruff
       - id: ruff-format
@@ -29,7 +29,7 @@ repos:
           - tomli
 
   - repo: https://github.com/tox-dev/pyproject-fmt
-    rev: "v2.4.3"
+    rev: "v2.5.0"
     hooks:
       - id: pyproject-fmt
 
@@ -42,7 +42,7 @@ repos:
         pass_filenames: false
 
   - repo: https://github.com/abravalheri/validate-pyproject
-    rev: v0.22
+    rev: v0.23
     hooks:
       - id: validate-pyproject
 

blockchain/proof_of_stake.py

@@ -0,0 +1,40 @@
+import random
+
+
+class Validator:
+    def __init__(self, name: str, stake: int) -> None:
+        """
+        Initializes a new validator with a given name and stake.
+
+        Args:
+            name (str): The name of the validator.
+            stake (int): The amount of stake the validator has.
+        """
+        self.name = name
+        self.stake = stake
+
+
+def choose_validator(validators: list[Validator]) -> Validator:
+    """
+    Selects a validator to create the next block based on the weight of their stake.
+
+    The higher the stake, the greater the chance to be selected.
+
+    Args:
+        validators (list[Validator]): A list of Validator objects.
+
+    Returns:
+        Validator: The selected validator based on weighted random selection.
+
+    Example:
+        >>> validators = [Validator("Alice", 50), Validator("Bob", 30)]
+        >>> chosen = choose_validator(validators)
+        >>> isinstance(chosen, Validator)
+        True
+    """
+    total_stake = sum(v.stake for v in validators)
+    weighted_validators = [(v, v.stake / total_stake) for v in validators]
+    selected = random.choices(
+        [v[0] for v in weighted_validators], weights=[v[1] for v in weighted_validators]
+    )
+    return selected[0]

blockchain/proof_of_work.py

@@ -0,0 +1,29 @@
+import hashlib
+
+
+def proof_of_work(difficulty: int) -> int:
+    """
+    Simulates a Proof of Work mining process.
+
+    The miner must find a nonce such that the hash of the nonce starts
+    with a specific number of leading zeros (difficulty).
+
+    Args:
+        difficulty (int): The number of leading zeros required in the hash.
+
+    Returns:
+        int: The nonce value that solves the puzzle.
+
+    Example:
+        >>> result = proof_of_work(2)  # Difficulty of 2 should be fast
+        >>> isinstance(result, int)
+        True
+    """
+    prefix = "0" * difficulty
+    nonce = 0
+
+    while True:
+        hash_result = hashlib.sha256(f"{nonce}".encode()).hexdigest()
+        if hash_result.startswith(prefix):
+            return nonce
+        nonce += 1

data_structures/arrays/sudoku_solver.py

@@ -172,7 +172,7 @@ def solved(values):
 
 def from_file(filename, sep="\n"):
     "Parse a file into a list of strings, separated by sep."
-    return open(filename).read().strip().split(sep)  # noqa: SIM115
+    return open(filename).read().strip().split(sep)
 
 
 def random_puzzle(assignments=17):

scripts/validate_filenames.py

@@ -1,4 +1,4 @@
-#!/usr/bin/env python3
+#!python
 import os
 
 try: