由于Tushare系统和PTrade系统上海市场的后缀不一致，比较容易造成客户在读取数据出现错误。我们特意编写一个函数可以把Tushare和PTrade的后缀相互转换。而且还能转换成PTrade系统的四位后缀。

code_switch(stock_list,end=0):

#转换为对应数据（需要指定参数数，入参0、2、4,其中0为转换成Tushare数据、2为转换成PTrade后缀为两位的数据、4为转换成PTrade后缀为四位的数据）

示例：
1、Ptrade的2或者4位后缀转换成Tushare的2位后缀的用法：
stocks = ['300560.SZ','000977.SZ','002261.SZ','600895.SS','603322.SS','300418.SZ','603501.SS','300735.SZ','600203.SS','301013.SZ','300134.SZ','002456.SZ']
TScode_list = code_switch(stocks,0)
print(TScode_list)
输出：['300560.SZ', '000977.SZ', '002261.SZ', '600895.SH', '603322.SH', '300418.SZ', '603501.SH', '300735.SZ', '600203.SH', '301013.SZ', '300134.SZ', '002456.SZ']

stocks =
['300560.XSHE', '000977.XSHE', '002261.XSHE', '600895.XSHG', '603322.XSHG', '300418.XSHE', '603501.XSHG', '300735.XSHE', '600203.XSHG', '301013.XSHE', '300134.XSHE', '002456.XSHE']

TScode_list = code_switch(stocks,0)
print(TScode_list)
输出：['300560.SZ', '000977.SZ', '002261.SZ', '600895.SH', '603322.SH', '300418.SZ', '603501.SH', '300735.SZ', '600203.SH', '301013.SZ', '300134.SZ', '002456.SZ']


2、Ptrade的4位后缀或者Tushare的2位后缀转换成Ptrade的2位后缀的用法：

stocks =
['300560.XSHE', '000977.XSHE', '002261.XSHE', '600895.XSHG', '603322.XSHG', '300418.XSHE', '603501.XSHG', '300735.XSHE', '600203.XSHG', '301013.XSHE', '300134.XSHE', '002456.XSHE']

code2 = code_switch(stocks,2)
print(code2)

输出：['300560.SZ', '000977.SZ', '002261.SZ', '600895.SS', '603322.SS', '300418.SZ', '603501.SS', '300735.SZ', '600203.SS', '301013.SZ', '300134.SZ', '002456.SZ']

stocks = ['300560.SZ', '000977.SZ', '002261.SZ', '600895.SH', '603322.SH', '300418.SZ', '603501.SH', '300735.SZ', '600203.SH', '301013.SZ', '300134.SZ', '002456.SZ']

code_2 = code_switch(stocks,2)
print(code_2)
输出：['300560.SZ', '000977.SZ', '002261.SZ', '600895.SS', '603322.SS', '300418.SZ', '603501.SS', '300735.SZ', '600203.SS', '301013.SZ', '300134.SZ', '002456.SZ']

3、Ptrade的2位后缀或者Tushare的2位后缀转换成Ptrade的4位后缀的用法：

stocks = ['300560.SZ','000977.SZ','002261.SZ','600895.SS','603322.SS','300418.SZ','603501.SS','300735.SZ','600203.SS','301013.SZ','300134.SZ','002456.SZ']
code_4 = code_switch(stocks,4)
print(code_4)
输出：['300560.XSHE', '000977.XSHE', '002261.XSHE', '600895.XSHG', '603322.XSHG', '300418.XSHE', '603501.XSHG', '300735.XSHE', '600203.XSHG', '301013.XSHE', '300134.XSHE', '002456.XSHE']

stocks = ['300560.SZ', '000977.SZ', '002261.SZ', '600895.SH', '603322.SH', '300418.SZ', '603501.SH', '300735.SZ', '600203.SH', '301013.SZ', '300134.SZ', '002456.SZ']
code_4 = code_switch(stocks,4)
print(code_4)
输出：['300560.XSHE', '000977.XSHE', '002261.XSHE', '600895.XSHG', '603322.XSHG', '300418.XSHE', '603501.XSHG', '300735.XSHE', '600203.XSHG', '301013.XSHE', '300134.XSHE', '002456.XSHE']


4、其他参数输入情况

stocks = ['300560.SZ', '000977.SZ', '002261.SZ', '600895.SH', '603322.SH', '300418.SZ', '603501.SH', '300735.SZ', '600203.SH', '301013.SZ', '300134.SZ', '002456.SZ']
code_5 = code_switch(stocks,5)
print(code_5)
输出：转换后缀入参有误，请输入数字0、2或者4