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Solve the following problem using Python, implementing the functions described below, one line at a time
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<USER_TASK:>
Description:
 def set_user_password(self, username, password):
 """Change the password of an existing user. :param username: the username who's password is being changed :type username: str :param password: the new password for the user :type password: str """

        text = "SET PASSWORD FOR {0} = {1}".format(
            quote_ident(username), quote_literal(password))
        self.query(text)