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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 last_modified(self):
 """Get the HTTP-datetime of when the collection was modified."""

        # FIXME: Make this sensible
        last_modified = time.strftime(
            "%a, %d %b %Y %H:%M:%S GMT",
            time.gmtime(time.time()))
        return last_modified