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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 to_csv(self, filename: str, latexify_names: bool = False):
 """ Exports PDEntries to a csv Args: filename: Filename to write to. entries: PDEntries to export. latexify_names: Format entry names to be LaTex compatible, e.g., Li_{2}O """


        elements = set()
        for entry in self.entries:
            elements.update(entry.composition.elements)
        elements = sorted(list(elements), key=lambda a: a.X)
        writer = csv.writer(open(filename, "w"), delimiter=unicode2str(","),
                            quotechar=unicode2str("\""),
                            quoting=csv.QUOTE_MINIMAL)
        writer.writerow(["Name"] + elements + ["Energy"])
        for entry in self.entries:
            row = [entry.name if not latexify_names
                   else re.sub(r"([0-9]+)", r"_{\1}", entry.name)]
            row.extend([entry.composition[el] for el in elements])
            row.append(entry.energy)
            writer.writerow(row)