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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 inspect(self, refresh=True):
 """ provide metadata about the image; flip refresh=True if cached metadata are enough :param refresh: bool, update the metadata with up to date content :return: dict """

        if refresh or not self._inspect_data:
            identifier = self._id or self.get_full_name()
            if not identifier:
                raise ConuException("This image does not have a valid identifier.")
            self._inspect_data = self.d.inspect_image(identifier)
        return self._inspect_data