怎么是区块链技术

import hashlib
import time

class Block:
    def __init__(self, index, previous_hash, timestamp, data, hash):
        self.index = index
        self.previous_hash = previous_hash
        self.timestamp = timestamp
        self.data = data
        self.hash = hash

def calculate_hash(index, previous_hash, timestamp, data):
    value = str(index) + previous_hash + str(timestamp) + data
    return hashlib.sha256(value.encode('utf-8')).hexdigest()

def create_genesis_block():
    timestamp = int(time.time())
    return Block(0, "0", timestamp, "Genesis Block", calculate_hash(0, "0", timestamp, "Genesis Block"))

def create_new_block(previous_block, data):
    index = previous_block.index + 1
    timestamp = int(time.time())
    hash = calculate_hash(index, previous_block.hash, timestamp, data)
    return Block(index, previous_block.hash, timestamp, data, hash)

# 示例使用
genesis_block = create_genesis_block()
second_block = create_new_block(genesis_block, "This is the second block")

print("Genesis Block Hash:", genesis_block.hash)
print("Second Block Hash:", second_block.hash)