MinimalBlock object in minimal blockchain

MinimalBlock.py

import hashlib

class MinimalBlock():
    def __init__(self, index, timestamp, data, previous_hash):
        self.index = index
        self.timestamp = timestamp
        self.data = data
        self.previous_hash = previous_hash
        self.hash = self.hashing()
    
    def hashing(self):
        key = hashlib.sha256()
        key.update(str(self.index).encode('utf-8'))
        key.update(str(self.timestamp).encode('utf-8'))
        key.update(str(self.data).encode('utf-8'))
        key.update(str(self.previous_hash).encode('utf-8'))
        return key.hexdigest()