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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 container_name(self):
 """ The container_name is the concatenation of ``image_name`` and a uuid1 string We also remove the url portion of the ``image_name`` before using it. """

        if getattr(self, "_container_name", NotSpecified) is NotSpecified:
            self.container_name = "{0}-{1}".format(self.image_name.replace("/", "--").replace(":", "---"), str(uuid.uuid1()).lower())
        return self._container_name