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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 add_message(self, msg_content, folder, **kwargs):
 """ Inject a message :params string msg_content: The entire message's content. :params string folder: Folder pathname (starts with '/') or folder ID """

        content = {'m': kwargs}
        content['m']['l'] = str(folder)
        content['m']['content'] = {'_content': msg_content}

        return self.request('AddMsg', content)