也可以使用tuple()创建一个元组: 不指定参数时,返回一个空元组 使用tuple作为参数时,返回该参数的浅拷贝 其他参数时,尝试将给定的对象转换为tuple类型 1.1.2 元组索引和分片 代码语言:javascript 代码运行次数:0 运行 AI代码解释 tup=('first',5,'white','dog')print(tup[1])print(tup[-2])print(tup[1:...
6.《Python Programming: An Introduction to Computer Science》,John Zelle:这本书旨在教授Python编程语言及计算机科学的基本原理,适合具备基础编程知识的读者。 7.《Head First Python: A Brain-Friendly Guide》,Paul Barry:这是一本图文并茂、通俗易懂的Python入门书籍,非常适合初学者。 六、结语 Python入门的重要...
(c1.value) c2 = sheet['D4'] print(c2.value) """ # 3.第N行所有的单元格 """ for cell in sheet[1]: print(cell.value) """ # 4.所有行的数据(获取某一行数据) """ for row in sheet.rows: print(row[0].value, row[1].value) """ # 5.获取所有列的数据 """ for col in ...
popitem()methodofbuiltins.dictinstanceRemoveandreturna(key,value)pairasa2-tuple.PairsarereturnedinLIFO(last-in,first-out)order.RaisesKeyErrorifthedictisempty. LIFO ,即“Last in, First out”,译为“后进先出”,这是计算机科学中插入、删除数据一种原则,例如,一种名为栈( Stack )的数据结构,只能在栈...
print(eval(f'{firsts_num}{item}{second_num}')) # 323. exec(): exec(object[, globals[, locals]])描述: 执行储存在字符串或文件中的Python语句,相比于eval,exec可以执行更复杂的Python代码。参数:object-- 要执行的表达式。globals -- 可选。包含全局参数的字典。locals -- 可选。包含局部参数的...
classCustomTuple(tuple):def__class_getitem__(cls,index):ifindex==0:return'First element'elifindex==1:return'Second element'else:return'Invalid index'# 创建自定义元组对象custom_tuple=CustomTuple()# 使用索引访问元素print(custom_tuple[0])# 输出:First elementprint(custom_tuple[1])# 输出...
#Other functions for dictionarylang_dict = {'First': 'Python','Second': 'Java', 'Third': 'Ruby'}print(lang_dict.keys()) #get keysprint(lang_dict.values()) #get valuesprint(lang_dict.items()) #get key-value pairsprint(lang_dict.get('First'))Output:dict_keys(['First', 'Second'...
n - 1. This is useful if you areconcatenating objects where the concatenation axis does not havemeaningful indexing information. Note the index values on the otheraxes are still respected in the join.keys : sequence, default NoneIf multiple levels passed, should contain tuples. Constructhierarchic...
""" T.count(value) -> integer -- return number of occurrences of value """ return 0 def index(self, value, start=None, stop=None): # real signature unknown; restored from __doc__ """ T.index(value, [start, [stop]]) -> integer -- return first index of value. ...
integer, must be return value of previous stamp() call.|| Example (for a Turtle instance named turtle):| >>> turtle.color("blue")| >>> astamp = turtle.stamp()| >>> turtle.fd(50)| >>> turtle.clearstamp(astamp)|| clearstamps(self, n=None)| Delete all or first/last n of ...