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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 _unlock(self):
 """ Unlock this keyring by getting the password for the keyring from the user. """

        self.keyring_key = getpass.getpass(
            'Please enter password for encrypted keyring: ')
        try:
            ref_pw = self.get_password('keyring-setting', 'password reference')
            assert ref_pw == 'password reference value'
        except AssertionError:
            self._lock()
            raise ValueError("Incorrect Password")