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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 _export_table(table, fname):
 """Export DataFrame to .csv"""

    import os.path as op
    extension = op.splitext(fname.lower())[1]
    if extension == '':
        fname = fname + '.csv'
    table.to_csv(fname, index=None, sep=',', encoding='utf-8',
                 float_format='%.4f', decimal='.')