100个python的基本语法知识【下】

50. 压缩文件：

import zipfile


with zipfile.ZipFile("file.zip", "r") as zip_ref:
    zip_ref.extractall("extracted")

51. 数据库操作：

import sqlite3

conn = sqlite3.connect("my_database.db")
cursor = conn.cursor()
cursor.execute("CREATE TABLE IF NOT EXISTS users (id INTEGER PRIMARY KEY, name TEXT)")
conn.commit()
conn.close()

52. 网络请求：

import requests
response = requests.get("https://www.example.com")

53. 多线程：

import threading

def my_thread():
    print("Thread running")

thread = threading.Thread(target=my_thread)
thread.start()
thread.join()

54. 多进程：

import multiprocessing
def my_process():
    print("Process running")
process = multiprocessing.Process(target=my_process)
process.start()
process.join()

55. 进程池：

from multiprocessing import Pool
def my_function(x):
    return x*x
with Pool(5) as p:
    print(p.map(my_function, [1, 2, 3]))

56. 队列：

from queue import Queue
q = Queue()
q.put(1)
q.put(2)
q.get()

57. 协程：

import asyncio
async def my_coroutine():
    await asyncio.sleep(1)
    print("Coroutine running")

asyncio.run(my_coroutine())

58. 异步IO：

import aiohttp
import asyncio

async def fetch(url):
    async with aiohttp.ClientSession() as session:
        async with session.get(url) as response:
            return await response.text()

loop = asyncio.get_event_loop()
loop.run_until_complete(fetch("https://www.example.com"))

59. 信号处理：

import signal


def handler(signum, frame):
    print("Signal handler called with signal", signum)

signal.signal(signal.SIGINT, handler)

60. 装饰器的实现：

def my_decorator(func):
    def wrapper(*args, **kwargs):
        print("Before function call")
        result = func(*args, **kwargs)
        print("After function call")
        return result
    return wrapper

61. 基于类的装饰器：

class MyDecorator:
    def __init__(self, func):
        self.func = func

    def __call__(self, *args, **kwargs):
        print("Before function call")
        result = self.func(*args, **kwargs)
        print("After function call")
        return result

62. 模块和包的导入：

from my_package import my_module

63. 相对导入：

from .my_module import my_function

64. 集合操作：

set1 = {1, 2, 3}
set2 = {2, 3, 4}
set1 & set2  # 交集
set1 | set2  # 并集
set1 - set2  # 差集

65. 集合方法：

my_set.add(5)
my_set.remove(5)

66. 字典方法：

my_dict.keys()
my_dict.values()
my_dict.items()

67. 对象方法：

class MyClass:
    def method(self):
        pass

obj = MyClass()
obj.method()

68. 类方法：

class MyClass:
    @classmethod
    def method(cls):
        pass

69. 静态方法：

class MyClass:
    @staticmethod
    def method():
        pass

70. 上下文管理器的实现：

class MyContextManager:
    def __enter__(self):
        pass

    def __exit__(self, exc_type, exc_val, exc_tb):
        pass

with MyContextManager():
    pass

71. 元类：

class MyMeta(type):
    def __new__(cls, name, bases, dct):
        return super().__new__(cls, name, bases, dct)

72. 装饰器链：

@decorator1
@decorator2
def my_function():
    pass

73. 属性的getter和setter：

class MyClass:
    def __init__(self, value):
        self._value = value
    @property
    def value(self):
        return self._value
    @value.setter
    def value(self, new_value):
        self._value = new_value

74. 文件操作：

with open("file.txt", "r") as file:
    content = file.read()

75. with语句：

with open("file.txt", "r") as file:
    content = file.read()

76. yield语句：

def my_generator():
    yield 1
    yield 2
    yield 3

77. 生成器表达式：

gen = (x**2 for x in range(10))

78. 列表方法：

my_list.append(5)
my_list.remove(5)

79. 元组解包：

a, b, c = (1, 2, 3)

80. 字典解包：

def my_function(a, b, c):
    pass

my_dict = {'a': 1, 'b': 2, 'c': 3}
my_function(**my_dict)

81. 循环中断：

for i in range(10):
    if i == 5:
        break

82. 循环跳过：

for i in range(10):
    if i == 5:
        continue

83. 异步编程：

import asyncio

async def my_coroutine():
    await asyncio.sleep(1)

asyncio.run(my_coroutine())

84. 类型检查：

isinstance(5, int)

85. 序列化和反序列化：

import pickle
data = {"name": "John", "age": 30}
with open("data.pkl", "wb") as file:
    pickle.dump(data, file)

with open("data.pkl", "rb") as file:
    data = pickle.load(file)

86. 文件读取模式：

with open("file.txt", "r") as file:
    content = file.read()

87. 文件写入模式：

with open("file.txt", "w") as file:
    file.write("Hello, World!")

88. 上下文管理器：

with open("file.txt", "r") as file:
    content = file.read()

89. 命令行参数解析：

import argparse

parser = argparse.ArgumentParser(description="My program")
parser.add_argument("name", type=str, help="Your name")
args = parser.parse_args()

90. 模块导入：

import my_module

91. 包导入：

from my_package import my_module

92. 包的相对导入：

from .my_module import my_function

93. 动态属性：

class MyClass:
    def __init__(self):
        self.dynamic_attr = "I am dynamic"

94. 动态方法：

def dynamic_method(self):
    return "I am dynamic"

MyClass.dynamic_method = dynamic_method

95. 类的单例模式：

class Singleton:
    _instance = None

96. 类的工厂模式：

class Factory:
    def create(self, type):
        if type == "A":
            return A()
        elif type == "B":
            return B()

97. 依赖注入：

class Service:
    def __init__(self, dependency):
        self.dependency = dependency

98. 抽象类：

from abc import ABC, abstractmethod
class AbstractClass(ABC):
    @abstractmethod
    def my_method(self):
        pass

99. 接口：

from abc import ABC, abstractmethod
class Interface(ABC):
    @abstractmethod
    def method(self):
        pass