python元组实战，两分钟搞懂：

Python 3.7.9 (tags/v3.7.9:13c94747c7, Aug 17 2020, 18:58:18) [MSC v.1900 64 bit (AMD64)] on win32
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>>> t1 = (10, 20, 30)
>>> print(t1)

(10, 20, 30)
>>> print(type(t1))
<class 'tuple'>
>>> t2 = (10,)
>>> print(type(t2))
<class 'tuple'>
>>> 
>>> t4 = ('aaa')
>>> print(type(t4))
<class 'str'>
>>> t1 = ('aa', 'bb', 'cc', 'bb')
>>> print(t1[0])
aa
>>> print(t1.index('bb'))
1
>>> print(t1.index('bbb'))

Traceback (most recent call last):
  File "<pyshell#11>", line 1, in <module>
    print(t1.index('bbb'))
ValueError: tuple.index(x): x not in tuple
>>> count()
Traceback (most recent call last):
  File "<pyshell#12>", line 1, in <module>
    count()
NameError: name 'count' is not defined
>>>  print(t1.count('aa'))
 
SyntaxError: unexpected indent
>>> print(t1.count('aa'))    #统计元素个数
1
>>> print(t1.count('aaa'))
0
>>> print(len(t1))  #输出元组的长度
>>>4