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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 merge_true_table():
 """Merge all true table into single excel file. """

    writer = pd.ExcelWriter("True Table.xlsx")
    for p in Path(__file__).parent.select_by_ext(".csv"):
        df = pd.read_csv(p.abspath, index_col=0)
        df.to_excel(writer, p.fname, index=True)
    writer.save()