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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 send_knock(self, created=False):
 """ Send the knock in the associated channels Group """

        knock = self.as_knock(created)
        if knock:
            gr = Group('knocker-{0}'.format(knock['language']))
            gr.send({'text': json.dumps(knock)})