Stream.sample is not affected by processors

[roll]

Overview

Expected behavior:

    # Processors
    def only_first_row(extended_rows):
        for number, header, row in extended_rows:
            if number == 1:
                yield (number, header, row)

    # Get table
    table = topen('data/table.csv', post_parse=[only_first_row])

    # Make assertions
    assert table.sample == ['id', 'name'] # for now will return all table rows