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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 meta(name, value, scheme=None):
 """ Adds meta information to a class definition. @param name: name of the meta data class @type name: str or unicode @param value: metadata value @type value: str or unicode @param scheme: format information about the value @type scheme: str or unicode or None """

    annotate.injectClassCallback("meta", 3, "annotate_meta",
                                 name, value, scheme=scheme)