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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 open(self):
 """ Open a connection to the AMQP compliant broker. """

        self._connection = \
          amqp.Connection(host='%s:%s' % (self.hostname, self.port),
                          userid=self.username, password=self.password,
                          virtual_host=self.virtual_host, insist=False)
        self.channel = self._connection.channel()