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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 AddXrefTo(self, ref_kind, classobj, methodobj, offset):
 """ Creates a crossreference to another class. XrefTo means, that the current class calls another class. The current class should also be contained in the another class' XrefFrom list. :param REF_TYPE ref_kind: type of call :param classobj: :class:`ClassAnalysis` object to link :param methodobj: :param offset: Offset in the Methods Bytecode, where the call happens :return: """

        self.xrefto[classobj].add((ref_kind, methodobj, offset))