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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 _find_nml(self):
 """ Find the start and end of the embedded namelist. Returns ------- (int, int) start and end index for the namelist """

        nml_start = None
        nml_end = None
        for i in range(len(self.lines)):
            if self.lines[i].strip().startswith("&"):
                nml_start = i

            if self.lines[i].strip().startswith("/"):
                nml_end = i
        assert (
            nml_start is not None and nml_end is not None
        ), "Could not find namelist within {}".format(self.filepath)
        return nml_end, nml_start