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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_note(self, content):
 """Add a note to the project. .. warning:: Requires Todoist premium. :param content: The note content. :type content: str """

        args = {
            'project_id': self.id,
            'content': content
        }
        _perform_command(self.owner, 'note_add', args)