def split_file(filename, output_size=2000, max_rows=160000):
    with open(filename, encoding="utf8") as input_file:
        current_row = 1
        while current_row < max_rows:
            current_output_file_num = current_row // output_size
            output_filename = filename[:-4] + '_out_'
            output_filename += str(current_output_file_num)
            output_filename += ".csv"
            print(output_filename)
            with open(output_filename, 'w', encoding="utf8") as output_file:
                print("new file open")
                current_lines = 0
                while current_lines < output_size:
                    line = input_file.readline()
                    if not line:
                        break
                    else:
                        line = str(current_row) + ',' + line
                    output_file.write(line)
                    current_row += 1
                    current_lines += 1
                print("current file complete", current_lines, "lines in file")
                print("final_line:", line)
                if not line:
                    break