# 使用字典進行快速查找
sample_dict = {'a': 1, 'b': 2, 'c': 3}
if 'b' in sample_dict:
    print(sample_dict['b'])

# 列表推導式
squared_numbers = [x**2 for x in range(10)]

# 生成器表達式
even_numbers = (x for x in range(10) if x % 2 == 0)

# 裝飾器示例
def my_decorator(func):
    def wrapper():
        print("Something is happening before the function is called.")
        func()
        print("Something is happening after the function is called.")
    return wrapper

@my_decorator
def say_hello():
    print("Hello!")

# 上下文管理器示例
class MyContextManager:
    def __enter__(self):
        print("Entering the context")
    
    def __exit__(self, exc_type, exc_value, traceback):
        print("Exiting the context")

with MyContextManager() as cm:
    print("Inside the context")

import threading

def print_numbers():
    for i in range(5):
        print(i)

# 多線程示例
thread = threading.Thread(target=print_numbers)
thread.start()

# 函數(shù)式編程示例
def multiply_by(n):
    return lambda x: x * n

doubler = multiply_by(2)
print(doubler(5))  # Output: 10

# Lambda函數(shù)示例
my_function = lambda x: x * 2
print(my_function(3))  # Output: 6

# collections模塊示例
from collections import Counter

my_list = [1, 1, 2, 3, 3, 3, 4, 4, 5]
counter = Counter(my_list)
print(counter)  # Output: Counter({3: 3, 1: 2, 4: 2, 2: 1, 5: 1})

# os模塊示例
import os

file_list = os.listdir('.')
print(file_list)

# 文件讀取示例
with open('example.txt', 'r') as file:
    content = file.read()
    print(content)

# 文件寫入示例
with open('example_write.txt', 'w') as file:
    file.write('Hello, Python!')

# 調試工具示例
import pdb

def some_function():
    x = 10
    pdb.set_trace()
    print("End")

# 性能優(yōu)化示例
import timeit

code_to_test = """
# your code here
"""

execution_time = timeit.timeit(code_to_test, number=100)
print(execution_time)

# 測試用例示例（使用unittest）
import unittest

def add(a, b):
    return a + b

class TestAddFunction(unittest.TestCase):
    def test_add(self):
        self.assertEqual(add(3, 4), 7)
        self.assertEqual(add(0, 0), 0)

if __name__ == '__main__':
    unittest.main()

# asyncio示例
import asyncio

async def my_coroutine():
    await asyncio.sleep(1)
    print("Task complete!")

asyncio.run(my_coroutine())

# 多線程/多進程示例
import threading

def print_numbers():
    for i in range(5):
        print(i)

thread = threading.Thread(target=print_numbers)
thread.start()