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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 _load_kgXref(filename):
 """ Load UCSC kgXref table. Parameters filename : str path to kgXref file Returns ------- df : pandas.DataFrame kgXref table if loading was successful, else None """

        try:
            df = pd.read_table(
                filename,
                names=[
                    "kgID",
                    "mRNA",
                    "spID",
                    "spDisplayID",
                    "geneSymbol",
                    "refseq",
                    "protAcc",
                    "description",
                    "rfamAcc",
                    "tRnaName",
                ],
                index_col=0,
                dtype=object,
            )
            return df
        except Exception as err:
            print(err)
            return None