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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 _api_path(self, item):
 """Get the API path for the current cursor position."""

        if self.base_url is None:
            raise NotImplementedError("base_url not set")
        path = "/".join([x.blob["id"] for x in item.path])
        return "/".join([self.base_url, path])