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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 block_user(self, username, domain):
 """Block the specified user. The default implementation calls :py:func:`~xmpp_backends.base.XmppBackendBase.set_password` with a random password. :param username: The username of the user. :type username: str :param domain: The domain of the user. :type domain: str """

        self.set_password(username, domain, self.get_random_password())