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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_tag(self, tag):
 # type: (str) -> bool """Add a tag Args: tag (str):
 Tag to add Returns: bool: True if tag added or False if tag already present """

        tags = self.data.get('tags', None)
        if tags:
            if tag in [x['name'] for x in tags]:
                return False
        else:
            tags = list()
        tags.append({'name': tag})
        self.data['tags'] = tags
        return True