convert data in deal_level_data.csv to quarter_level_data.csv.

Write a code to convert data in deal_level_data.csv to quarter_level_data.csv.

   The code must directly read the input file and write the output file. 

如何把横向的多个数据以竖向方式写到另一个csv file里面？
已完成读取 deal_level_data 有[3005 rows x 1467 columns]
quarter_level_data 有[75125 rows x 42 columns]