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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 check_unique_tags(tag_list):
 """Checks that tag list contains each set of tags only once."""

  frozen_tags_seen = set()
  for tags in tag_list:
    frozen_tags = frozenset(tags)
    if frozen_tags in frozen_tags_seen:
      raise ValueError("Tags %r used repeatedly" % tags)
    frozen_tags_seen.add(frozen_tags)