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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 response(self, text, response_type='ephemeral', attachments=None):
 """Return a response with json format :param text: the text returned to the client :param response_type: optional. When `in_channel` is assigned, both the response message and the initial message typed by the user will be shared in the channel. When `ephemeral` is assigned, the response message will be visible only to the user that issued the command. :param attachments: optional. A list of additional messages for rich response. """

        from flask import jsonify
        if attachments is None:
            attachments = []

        data = {
            'response_type': response_type,
            'text': text,
            'attachments': attachments,
        }
        return jsonify(**data)