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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 ChangePassword(self, password_old, password_new):
 """ Change the password used to protect the private key. Args: password_old (str):
 the current password used to encrypt the private key. password_new (str):
 the new to be used password to encrypt the private key. Returns: bool: whether the password has been changed """

        if not self.ValidatePassword(password_old):
            return False

        if isinstance(password_new, str):
            password_new = password_new.encode('utf-8')

        password_key = hashlib.sha256(password_new)
        self.SaveStoredData("PasswordHash", password_key)
        self.SaveStoredData("MasterKey", AES.new(self._master_key, AES.MODE_CBC, self._iv))

        return True