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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 _get_ctx(self):
 """ Get web.ctx object for the Template helper """

        if self._WEB_CTX_KEY not in web.ctx:
            web.ctx[self._WEB_CTX_KEY] = {
                "javascript": {"footer": [], "header": []},
                "css": []}
        return web.ctx.get(self._WEB_CTX_KEY)