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Custom Python Bech32 Auditor

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Custom Python Bech32 Auditor

In this final guide, we will build a Python script that performs the 8-to-5 Bit Conversion required for Bech32. This script will take a hexadecimal hash and convert it into the Base32 characters used in modern Bitcoin addresses.

The Bech32 Bit Auditor

# The Bech32 Base32 Alphabet
CHARSET = "qpzry9x8gf2tvdw0s3jn54khce6mua7l"

def convert_8_to_5(data_bytes):
    """Converts 8-bit bytes into 5-bit chunks."""
    acc = 0
    bits = 0
    res = []
    for value in data_bytes:
        acc = (acc \u003c\u003c 8) | value
        bits += 8
        while bits \u003e= 5:
            bits -= 5
            res.append((acc \u003e\u003e bits) \u0026 31)

    # Handle remaining bits (padding)
    if bits \u003e 0:
        res.append((acc \u003c\u003c (5 - bits)) \u0026 31)
    return res

def audit_bech32_encoding(hex_hash):
    print(f"--- Bech32 Encoding Audit ---")
    print(f"[*] Input Hex: {hex_hash}")

    # 1. Convert hex to bytes
    raw_bytes = bytes.fromhex(hex_hash)

    # 2. Perform 8-to-5 conversion
    five_bit_chunks = convert_8_to_5(raw_bytes)
    print(f"[*] 5-bit Groups: {len(five_bit_chunks)}")

    # 3. Map to characters
    encoded = "".join([CHARSET[c] for c in five_bit_chunks])
    print(f"[SUCCESS] Encoded Data: {encoded}")

    # Note: A real address would prepend 'bc1q' and append a 6-char checksum
    print(f"[*] Simulated Address: bc1q{encoded}xxxxxx")

# --- Simulation ---

# A standard 20-byte Public Key Hash
test_hash = "79be667ef9dcbbac55a06295ce870b07029bfc01"
audit_bech32_encoding(test_hash)

How to Run the Auditor

  1. Ensure you have Python 3 installed.

  2. Copy the code into a file named bech32_auditor.py.

  3. Run it using python3 bech32_auditor.py.

Technical Takeaways

  1. Alignment: Notice how a 20-byte hash (160 bits) results in exactly 32 Base32 characters ($160 / 5 = 32$). This perfect alignment is one reason why Bech32 was chosen.

  2. Bitwise Performance: Unlike Base58, which requires heavy division, this script only uses shifts (\u003c\u003c) and masks (\u0026). It is extremely fast.

  3. Missing Checksum: In a real Bitcoin wallet, the xxxxxx at the end would be a BCH Checksum derived from the HRP and the data to ensure validity.

Congratulations! You have completed the Bech32 Encoding (The SegWit Standard) module. You now understand the bit-level transformation that powers modern Bitcoin commerce.

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Ethereum: 0x578417C51783663D8A6A811B3544E1f779D39A85
Bitcoin: bc1q77k9e95rn669kpzyjr8ke9w95zhk7pa5s63qzz
Solana: 4ycT2ayqeMucixj3wS8Ay8Tq9NRDYRPKYbj3UGESyQ4J
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