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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 _conv(self, data):
 """Convert each input to appropriate for table outplot"""

        if isinstance(data, pd.Series):
            if data.name is None:
                data = data.to_frame(name='')
            else:
                data = data.to_frame()
        data = data.fillna('NaN')
        return data