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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 get_source_class(self, _class):
 """ Return the Java source code of a whole class :param _class: `ClassDefItem` object, to get the source from :return: """

        if not _class.get_name() in self.classes:
            return ""
        return self.classes[_class.get_name()]