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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 getWorksheetServices(self):
 """get list of analysis services present on this worksheet """

        services = []
        for analysis in self.getAnalyses():
            service = analysis.getAnalysisService()
            if service and service not in services:
                services.append(service)
        return services