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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 identify(s):
 """Identify what kind of Chinese characters a string contains. *s* is a string to examine. The string's Chinese characters are tested to see if they are compatible with the Traditional or Simplified characters systems, compatible with both, or contain a mixture of Traditional and Simplified characters. The :data:`TRADITIONAL`, :data:`SIMPLIFIED`, :data:`BOTH`, or :data:`MIXED` constants are returned to indicate the string's identity. If *s* contains no Chinese characters, then :data:`UNKNOWN` is returned. All characters in a string that aren't found in the CC-CEDICT dictionary are ignored. Because the Traditional and Simplified Chinese character systems overlap, a string containing Simplified characters could identify as :data:`SIMPLIFIED` or :data:`BOTH` depending on if the characters are also Traditional characters. To make testing the identity of a string easier, the functions :func:`is_traditional`, :func:`is_simplified`, and :func:`has_chinese` are provided. """

    chinese = _get_hanzi(s)
    if not chinese:
        return UNKNOWN
    if chinese.issubset(_SHARED_CHARACTERS):
        return BOTH
    if chinese.issubset(_TRADITIONAL_CHARACTERS):
        return TRADITIONAL
    if chinese.issubset(_SIMPLIFIED_CHARACTERS):
        return SIMPLIFIED
    return MIXED