你需要使第二个元素为1元组，例如:

a = ('2',)
b = 'z'
new = a + (b,)

>>> x = (u'2',)
>>> x += u"random string"

Traceback (most recent call last):
  File "<pyshell#11>", line 1, in <module>
    x += u"random string"
TypeError: can only concatenate tuple (not "unicode") to tuple
>>> x += (u"random string", )  # concatenate a one-tuple instead
>>> x
(u'2', u'random string')

你需要使第二个元素为1元组，例如:

a = ('2',)
b = 'z'
new = a + (b,)

从Python 3.5 (PEP 448)开始，你可以在元组、列表集和dict中进行解包:

a = ('2',)
b = 'z'
new = (*a, b)

最重要的是，添加到元组的最简单方法是用圆括号和逗号将添加的元素括起来。

t = ('a', 4, 'string')
t = t + (5.0,)
print(t)

out: ('a', 4, 'string', 5.0)

Tuple只允许向它添加Tuple。最好的方法是:

mytuple =(u'2',)
mytuple +=(new.id,)

我用下面的数据尝试了相同的场景，它似乎都工作得很好。

>>> mytuple = (u'2',)
>>> mytuple += ('example text',)
>>> print mytuple
(u'2','example text')