>>> abs(1)
>>> abs(-1)         # 求绝对值
>>> round(1.234,2)
1.23
>>> round(1.269,2)  # 四舍五入
1.27
>>> sum([1,2,3,4])
>>> sum((1,3,5,7))  # 接收数字组成的元组/列表

>>> def func():pass  
>>> callable(func)   # 判断一个变量是否可以调用 函数可以被调用
True
>>> a = 123          # 数字类型a不能被调用
>>> callable(a)
False
>>> chr(97)          # 将一个数字转换成一个字母
'a'
>>> chr(65)
'A'
>>> dir(123)         # 查看数字类型中含有哪些方法
['__abs__', '__add__', '__and__', '__bool__', '__ceil__', '__class__', '__delattr__', '__dir__', '__divmod__', '__doc__', '__eq__', '__float__', '__floor__', '__floordiv__', '__format__', '__ge__', '__getattribute__', '__getnewargs__', '__gt__', '__hash__', '__index__', '__init__', '__init_subclass__', '__int__', '__invert__', '__le__', '__lshift__', '__lt__', '__mod__', '__mul__', '__ne__', '__neg__', '__new__', '__or__', '__pos__', '__pow__', '__radd__', '__rand__', '__rdivmod__', '__reduce__', '__reduce_ex__', '__repr__', '__rfloordiv__', '__rlshift__', '__rmod__', '__rmul__', '__ror__', '__round__', '__rpow__', '__rrshift__', '__rshift__', '__rsub__', '__rtruediv__', '__rxor__', '__setattr__', '__sizeof__', '__str__', '__sub__', '__subclasshook__', '__truediv__', '__trunc__', '__xor__', 'bit_length', 'conjugate', 'denominator', 'from_bytes', 'imag', 'numerator', 'real', 'to_bytes']
>>> dir('abc')
['__add__', '__class__', '__contains__', '__delattr__', '__dir__', '__doc__', '__eq__', '__format__', '__ge__', '__getattribute__', '__getitem__', '__getnewargs__', '__gt__', '__hash__', '__init__', '__init_subclass__', '__iter__', '__le__', '__len__', '__lt__', '__mod__', '__mul__', '__ne__', '__new__', '__reduce__', '__reduce_ex__', '__repr__', '__rmod__', '__rmul__', '__setattr__', '__sizeof__', '__str__', '__subclasshook__', 'capitalize', 'casefold', 'center', 'count', 'encode', 'endswith', 'expandtabs', 'find', 'format', 'format_map', 'index', 'isalnum', 'isalpha', 'isascii', 'isdecimal', 'isdigit', 'isidentifier', 'islower', 'isnumeric', 'isprintable', 'isspace', 'istitle', 'isupper', 'join', 'ljust', 'lower', 'lstrip', 'maketrans', 'partition', 'replace', 'rfind', 'rindex', 'rjust', 'rpartition', 'rsplit', 'rstrip', 'split', 'splitlines', 'startswith', 'strip', 'swapcase', 'title', 'translate', 'upper', 'zfill']

>>> eval('1+2-3*4/5')  # 执行字符串数据类型的代码并且将值返回
0.6000000000000001
>>> exec('print(123)') # 执行字符串数据类型的代码但没有返回值
123

>>> enumerate(['apple','banana'],1)   # 会给列表中的每一个元素拼接一个序号
<enumerate object at 0x113753fc0>
>>> list(enumerate(['apple','banana'],1))
[(1, 'apple'), (2, 'banana')]

>>> max(1,2,3,)     # 求最小值
3
>>> min(2,1,3)      # 求最大值
1

>>> sorted([1, 4, 5, 12, 45, 67])  # 排序，并生成一个新的有序列表
[1, 4, 5, 12, 45, 67]

>>> sorted([1, 4, 5, 12, 45, 67], reverse=True)
[67, 45, 12, 5, 4, 1]

list1 = [
    {'name': 'Zoe', 'age': 30},
    {'name': 'Bob', 'age': 18},
    {'name': 'Tom', 'age': 22},
    {'name': 'Jack', 'age': 40},
]

ret = sorted(list1, key=lambda x: x['age'])
print(ret)

# [{'name': 'Bob', 'age': 18}, {'name': 'Tom', 'age': 22}, {'name': 'Zoe', 'age': 30}, {'name': 'Jack', 'age': 40}]

>>> x = ["a", "b", "c"]
>>> y = [1, 2, 3]
>>> a = list(zip(x, y))  # 合包
>>> a
[('a', 1), ('b', 2), ('c', 3)]
>>> b =list(zip(*a))  # 解包
>>> b
[('a', 'b', 'c'), (1, 2, 3)]

>>> x = [1, 3, 5, 7, 9]
>>> y = [2, 4, 6, 8]
>>> for m, n in zip(x, y):
...   print(m, n)
... 
2
4
6
8

>>> from itertools import zip_longest
>>> x = [1, 3, 5, 7, 9]
>>> y = [2, 4, 6, 8]
>>> for m, n in zip_longest(x, y):
...   print(m, n)
... 
2
4
6
8
None

>>> keys = ["name", "age", "salary"]
>>> values = ["Andy", 18, 50]
>>> d = dict(zip(keys, values))
>>> d
{'name': 'Andy', 'age': 18, 'salary': 50}