def add(value1,value2):

     #下面三个引号之间是测试代码，doctest会搜索这些代码并执行

     #并且根据执行结果与预期结果匹配程度来测试代码是否正确

     '''

     return the addition of two numbers or the concatenation of two string/list/tuple

     >>> add(3,5)

     8

     >>> add(3.0,5.0)

     8.0

     >>> add([1,2],[3,4])

     [1,2,3,4]

     >>> add((1,),(2,3,4))

     (1,2,3,4)

     >>> add(1,[3])

     TypeError

     >>> add(1,'2')

     TypeError

     >>> add([1],(2))

     TypeError

     >>> add('1234',[1,2,3,4])

     TypeError

     >>> add({1,2,3},{3,4,5})

     {1,2,3,4,5}

     >>> add({1:1},{2:2})

     TypeError

     '''

     #下面是正式的功能代码

     if type(value1) not in (int,float,str,list,tuple,set):

         raise TypeError('value1 and value2 must be the type of int,float,str,list,tuple,or set')

     if type(value1) != type(value2):

         raise TypeError('value1 and value2 must be of the same type')

     if type(value1) == set:

         return value1 | value2

     else:

         return value1 + value2

 if __name__ == '__main__':

     import doctest

     doctest.testmod()

     print(add(3,5))