types module name.

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)