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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 process_vasprun(self, dir_name, taskname, filename):
 """ Process a vasprun.xml file. """

        vasprun_file = os.path.join(dir_name, filename)
        if self.parse_projected_eigen and (self.parse_projected_eigen != 'final' or \
                             taskname == self.runs[-1]):
            parse_projected_eigen = True
        else:
            parse_projected_eigen = False
        r = Vasprun(vasprun_file,parse_projected_eigen=parse_projected_eigen)
        d = r.as_dict()
        d["dir_name"] = os.path.abspath(dir_name)
        d["completed_at"] = \
            str(datetime.datetime.fromtimestamp(os.path.getmtime(
                vasprun_file)))
        d["cif"] = str(CifWriter(r.final_structure))
        d["density"] = r.final_structure.density
        if self.parse_dos and (self.parse_dos != 'final' \
                               or taskname == self.runs[-1]):
            try:
                d["dos"] = r.complete_dos.as_dict()
            except Exception:
                logger.warning("No valid dos data exist in {}.\n Skipping dos"
                               .format(dir_name))
        if taskname == "relax1" or taskname == "relax2":
            d["task"] = {"type": "aflow", "name": taskname}
        else:
            d["task"] = {"type": taskname, "name": taskname}
        d["oxide_type"] = oxide_type(r.final_structure)
        return d