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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def from_master_secret_slow(cls, password, network=BitcoinMainNet):
 """ Generate a new key from a password using 50,000 rounds of HMAC-SHA256. This should generate the same result as bip32.org. WARNING: The security of this method has not been evaluated. """

        # Make sure the password string is bytes
        key = ensure_bytes(password)
        data = unhexlify(b"0" * 64)  # 256-bit 0
        for i in range(50000):
            data = hmac.new(key, msg=data, digestmod=sha256).digest()
        return cls.from_master_secret(data, network)