How to use the csvkit.grep.FilteringCSVReader function in csvkit

def test_no_header(self):
        fcr = FilteringCSVReader(iter(self.tab1), patterns={2: 'only'}, header=False)
        self.assertEqual(self.tab1[2], next(fcr))
        self.assertEqual(self.tab1[3], next(fcr))
        try:
            next(fcr)
            self.fail("Should be no more rows left.")
        except StopIteration:
            pass

def test_index_out_of_range(self):
        fcr = FilteringCSVReader(iter(self.tab2), patterns={3: '0'})
        self.assertEqual(self.tab2[0], next(fcr))
        self.assertEqual(self.tab2[4], next(fcr))
        try:
            next(fcr)
            self.fail("Should be no more rows left.")
        except StopIteration:
            pass

def test_any_match(self):
        fcr = FilteringCSVReader(iter(self.tab2), patterns={'age': 'only', 0: '2'}, any_match=True)
        self.assertEqual(self.tab2[0], next(fcr))
        self.assertEqual(self.tab2[2], next(fcr))
        self.assertEqual(self.tab2[4], next(fcr))
        try:
            next(fcr)
            self.fail("Should be no more rows left.")
        except StopIteration:
            pass

def test_inverse(self):
        fcr = FilteringCSVReader(iter(self.tab2), patterns=['1'], inverse=True)
        self.assertEqual(self.tab2[0], next(fcr))
        self.assertEqual(self.tab2[2], next(fcr))
        self.assertEqual(self.tab2[4], next(fcr))
        try:
            next(fcr)
            self.fail("Should be no more rows left.")
        except StopIteration:
            pass

def test_regex(self):
        pattern = re.compile(".*(Reader|Tribune).*")
        fcr = FilteringCSVReader(iter(self.tab1), patterns={1: pattern})

        self.assertEqual(self.tab1[0], next(fcr))
        self.assertEqual(self.tab1[1], next(fcr))
        self.assertEqual(self.tab1[3], next(fcr))
        self.assertEqual(self.tab1[4], next(fcr))
        try:
            next(fcr)
            self.fail("Should be no more rows left.")
        except StopIteration:
            pass

def test_multiline(self):
        table = [
            ['a', 'b'],
            ['1', 'foo\nbar']
        ]
        fcr = FilteringCSVReader(iter(table), patterns={'b': re.compile('bar')})
        self.assertEqual(table[0], next(fcr))
        self.assertEqual(table[1], next(fcr))
        try:
            next(fcr)
            self.fail("Should be no more rows left.")
        except StopIteration:
            pass

def test_any_match_and_inverse(self):
        fcr = FilteringCSVReader(iter(self.tab2), patterns={'age': 'only', 0: '2'}, any_match=True, inverse=True)
        self.assertEqual(self.tab2[0], next(fcr))
        self.assertEqual(self.tab2[1], next(fcr))
        self.assertEqual(self.tab2[3], next(fcr))
        try:
            next(fcr)
            self.fail("Should be no more rows left.")
        except StopIteration:
            pass

def test_pattern(self):
        fcr = FilteringCSVReader(iter(self.tab1), patterns=['1'])
        self.assertEqual(self.tab1[0], next(fcr))
        self.assertEqual(self.tab1[1], next(fcr))
        self.assertEqual(self.tab1[4], next(fcr))
        try:
            next(fcr)
            self.fail("Should be no more rows left.")
        except StopIteration:
            pass

def __init__(self, reader, patterns, header=True, any_match=False, inverse=False):
        super(FilteringCSVReader, self).__init__()

        self.reader = reader
        self.header = header

        if self.header:
            self.column_names = next(reader)

        self.any_match = any_match
        self.inverse = inverse
        self.patterns = standardize_patterns(self.column_names, patterns)

reader_kwargs['line_numbers'] = True

        rows, column_names, column_ids = self.get_rows_and_column_names_and_column_ids(**reader_kwargs)

        if self.args.regex:
            pattern = re.compile(self.args.regex)
        elif self.args.matchfile:
            lines = set(line.rstrip() for line in self.args.matchfile)

            def pattern(x):
                return x in lines
        else:
            pattern = self.args.pattern

        patterns = dict((column_id, pattern) for column_id in column_ids)
        filter_reader = FilteringCSVReader(rows, header=False, patterns=patterns, inverse=self.args.inverse)

        output = agate.csv.writer(self.output_file, **writer_kwargs)
        output.writerow(column_names)

        for row in filter_reader:
            output.writerow(row)