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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 validate_tag(key, value):
 """Validate a tag. Keys must be less than 128 chars and values must be less than 256 chars. """

    # Note, parse_sql does not include a keys if the value is an empty string
    # (e.g. 'key=&test=a'), and thus technically we should not get strings
    # which have zero length.
    klen = len(key)
    vlen = len(value)

    return klen > 0 and klen < 256 and vlen > 0 and vlen < 256