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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 add_outputs(self, **kwargs):
 """Add workflow outputs. The output type is added automatically, based on the steps in the steps library. Args: kwargs (dict):
 A dict containing ``name=source name`` pairs. ``name`` is the name of the workflow output (e.g., ``txt_files``) and source name is the name of the step that produced this output plus the output name (e.g., ``saf-to-txt/out_files``). """

        self._closed()

        for name, source_name in kwargs.items():
            obj = {}
            obj['outputSource'] = source_name
            obj['type'] = self.step_output_types[source_name]
            self.wf_outputs[name] = obj