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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 read_rawFilesTable(filename):
 """parse the 'rawFilesTable.txt' file into a pandas dataframe"""

    exp = pd.read_table(filename)
    expected_columns = {'File', 'Exists', 'Size', 'Data format', 'Parameter group', 'Experiment', 'Fraction'}
    found_columns = set(exp.columns)
    if len(expected_columns - found_columns) > 0:
        message = '\n'.join(['The raw files table has the wrong format!',
            'It should contain columns:',
            ', '.join(sorted(expected_columns)),
            'Found columns:',
            ', '.join(sorted(found_columns))])
        raise ValueError(message)
    exp['Raw file'] = exp['File'].apply(path.basename).apply(path.splitext).str.get(0)
    exp['Experiment'] = exp['Experiment'].astype(str)
    return exp