py 3.9 vs 3.11.8

vs/python/README.md

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+## 3.9
+```bash
+python3 --version
+Python 3.9.6
+
+for i in {1..5}; do python3 password_cracking_sequential.py; done
+
+Processing number combinations sequentially
+PASSWORD CRACKED: 87654321
+PROCESS TIME: 57.982330167
+Processing number combinations sequentially
+PASSWORD CRACKED: 87654321
+PROCESS TIME: 58.270694084
+Processing number combinations sequentially
+PASSWORD CRACKED: 87654321
+PROCESS TIME: 58.165215833999994
+Processing number combinations sequentially
+PASSWORD CRACKED: 87654321
+PROCESS TIME: 58.549774666999994
+Processing number combinations sequentially
+PASSWORD CRACKED: 87654321
+PROCESS TIME: 57.801265541
+```
+
+## 3.11.8
+```bash
+python3.11 --version
+Python 3.11.8
+
+python3.11 password_cracking_sequential.py
+➜  Chapter 2 git:(master) for i in {1..5}; do python3.11 password_cracking_sequential.py; done
+
+Processing number combinations sequentially
+PASSWORD CRACKED: 87654321
+PROCESS TIME: 48.50309233300504
+Processing number combinations sequentially
+PASSWORD CRACKED: 87654321
+PROCESS TIME: 48.76890112500405
+Processing number combinations sequentially
+PASSWORD CRACKED: 87654321
+PROCESS TIME: 48.461341125002946
+Processing number combinations sequentially
+PASSWORD CRACKED: 87654321
+PROCESS TIME: 48.608549166005105
+Processing number combinations sequentially
+PASSWORD CRACKED: 87654321
+PROCESS TIME: 48.863172917001066
+```

vs/python/password_cracking_sequential.py

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+#!/usr/bin/env python3.9
+
+"""Program for cracking the password consisting with only numbers using brute
+force approach sequentially"""
+
+import time
+import math
+import hashlib
+import typing as T
+
+
+def get_combinations(*, length: int, min_number: int = 0,
+                     max_number: T.Optional[int] = None) -> T.List[str]:
+    """Generate all possible password combinations"""
+    combinations = []
+    if not max_number:
+        # calculating maximum number based on the length
+        max_number = int(math.pow(10, length) - 1)
+
+    # go through all possible combinations in a given range
+    for i in range(min_number, max_number + 1):
+        str_num = str(i)
+        # fill in the missing numbers with zeros
+        zeros = "0" * (length - len(str_num))
+        combinations.append("".join((zeros, str_num)))
+    return combinations
+
+
+def get_crypto_hash(password: str) -> str:
+    """"Calculating cryptographic hash of the password"""
+    return hashlib.sha256(password.encode()).hexdigest()
+
+
+def check_password(expected_crypto_hash: str,
+                   possible_password: str) -> bool:
+    actual_crypto_hash = get_crypto_hash(possible_password)
+    # compare the resulted cryptographic hash with the one stored in the system
+    return expected_crypto_hash == actual_crypto_hash
+
+
+def crack_password(crypto_hash: str, length: int) -> None:
+    """Brute force the password combinations"""
+    print("Processing number combinations sequentially")
+    start_time = time.perf_counter()
+    combinations = get_combinations(length=length)
+    for combination in combinations:
+        if check_password(crypto_hash, combination):
+            print(f"PASSWORD CRACKED: {combination}")
+            break
+
+    process_time = time.perf_counter() - start_time
+    print(f"PROCESS TIME: {process_time}")
+
+
+if __name__ == "__main__":
+    crypto_hash = \
+        "e24df920078c3dd4e7e8d2442f00e5c9ab2a231bb3918d65cc50906e49ecaef4"
+    length = 8
+    crack_password(crypto_hash, length)