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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 start(self):
 """Start our welcome!"""

        if ('sasl' in self.capabilities.enabled and self._sasl_info and
                (not self.capabilities.available['sasl']['value'] or
                    (self.capabilities.available['sasl']['value'] and
                        self._sasl_info['method'] in
                        self.capabilities.available['sasl']['value']))):
            self.start_sasl()
        else:
            self.send('CAP', params=['END'])
            self.send_welcome()