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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 transform_dataframe(self, dataframe):
 """ Unstack the dataframe so header fields are across the top. """

        dataframe.columns.name = ""

        for i in range(len(self.get_header_fields())):
            dataframe = dataframe.unstack()

        # Remove blank rows / columns
        dataframe = dataframe.dropna(
            axis=0, how='all'
        ).dropna(
            axis=1, how='all'
        )
        return dataframe