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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 getTypesModuleName(self):
 """types module name. """

        if self.types_module_name is not None:
            return self.types_module_name

        name = GetModuleBaseNameFromWSDL(self._wsdl)
        if not name:
            raise WsdlGeneratorError, 'could not determine a service name'
        
        if self.types_module_suffix is None:
            return name

        return '%s%s' %(name, self.types_module_suffix)