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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 init_handler(self):
 """ Check self options. """

        assert self.options.get('host') and self.options.get('port'), "Invalid options"
        assert self.options.get('to'), 'Recipients list is empty. SMTP disabled.'
        if not isinstance(self.options['to'], (list, tuple)):
            self.options['to'] = [self.options['to']]