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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 get_nts_flat(self, hdrgo_prt=True, use_sections=True):
 """Return a flat list of sorted nts."""

        # Either there are no sections OR we are not using them
        if self.sectobj is None or not use_sections:
            return self.sortgos.get_nts_sorted(
                hdrgo_prt,
                hdrgos=self.grprobj.get_hdrgos(),
                hdrgo_sort=True)
        if not use_sections:
            return self.sectobj.get_sorted_nts_omit_section(hdrgo_prt, hdrgo_sort=True)
        return None