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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 csvdiff_cmd(index_columns, from_csv, to_csv, style=None, output=None, sep=',', quiet=False, ignore_columns=None, significance=None):
 """ Compare two csv files to see what rows differ between them. The files are each expected to have a header row, and for each row to be uniquely identified by one or more indexing columns. """


    if ignore_columns is not None:
        for i in ignore_columns:
            if i in index_columns:
                error.abort("You can't ignore an index column")

    ostream = (open(output, 'w') if output
               else io.StringIO() if quiet
               else sys.stdout)

    try:
        if style == 'summary':
            _diff_and_summarize(from_csv, to_csv, index_columns, ostream,
                                sep=sep, ignored_columns=ignore_columns,
                                significance=significance)
        else:
            compact = (style == 'compact')
            _diff_files_to_stream(from_csv, to_csv, index_columns, ostream,
                                  compact=compact, sep=sep, ignored_columns=ignore_columns,
                                  significance=significance)

    except records.InvalidKeyError as e:
        error.abort(e.args[0])

    finally:
        ostream.close()