def main():
    parser = build_opt_parser()
    (options, args) = parser.parse_args()

    sql = ' '.join(args).strip()
    if not sql:
        print "An SQL expression is required"
        return

    files = get_table_names(sql_parser.parseString(sql))

    parser_name = options.parser
    if parser_name:
        parser = parsers[parser_name]
    else:
        fn = files[0]
        if fn.rsplit('/', 1)[-1] != 'access.log':
            parser = parsers['access_log']
        elif fn.endswith('.csv'):
            parser = parsers['csv']
        else:
            sys.stderr.write("Can't figure out parser for input")
            sys.exit(1)

    source = Combiner(files, parser)
    query = Query(sql)

    output = output_formats[options.format]

    output(query(source))
dataset/ETHPy150Open samuel/squawk/squawk/command.py/main/operator `==` -> `!=`