Pythonのよく使う標準ライブラリ一覧と使い方の例 その3

import argparse

import argparse

# パーサーを作成
parser = argparse.ArgumentParser()

# 引数を追加
parser.add_argument('--name', default='名無し', help='名前を入力してください。')

# 引数をパース
args = parser.parse_args()

print(f"こんにちは、{args.name}!")

import argparse

# パーサーを作成
parser = argparse.ArgumentParser()

# 引数を追加
parser.add_argument('location', help='お住まいの地域を入力してください。')

# 引数をパース
args = parser.parse_args()

print(f"あなたは{args.location}に住んでいます。")

import getopt

import getopt
import sys

short_options = "ho:v"
long_options = ["help", "output=", "verbose"]

try:
    arguments, values = getopt.getopt(sys.argv[1:], short_options, long_options)
except getopt.error as err:
    print (str(err))
    sys.exit(2)

for current_argument, current_value in arguments:
    if current_argument in ("-v", "--verbose"):
        print ("enabling verbose mode")
    elif current_argument in ("-h", "--help"):
        print ("displaying help")
    elif current_argument in ("-o", "--output"):
        print (("enabling output mode (%s)") % (current_value))

import getopt
import sys

short_options = "o:"
long_options = ["output="]

try:
    arguments, values = getopt.getopt(sys.argv[1:], short_options, long_options)
except getopt.error as err:
    print (str(err))
    sys.exit(2)

for current_argument, current_value in arguments:
    if current_argument in ("-o", "--output"):
        print (("output file is (%s)") % (current_value))

import logging

# コンソールに表示されます
logging.warning('This is a warning message')

import logging

logging.basicConfig(level=logging.DEBUG,
                    format='%(asctime)s - %(name)s - %(levelname)s - %(message)s')

logging.warning('これは警告文です')

import logging

logging.basicConfig(filename='app.log',
                    level=logging.WARNING,
                    format='%(name)s - %(levelname)s - %(message)s')

logging.warning('これは警告文です')

import getpass

user = getpass.getuser()
password = getpass.getpass('Please enter your password: ')

print(f'User: {user}, Password: {"*" * len(password)}')

import getpass

password = getpass.getpass("パスワードを入力してください: ")
print("あなたのパスワードは", '*' * len(password))

import getpass

try:
    password = getpass.getpass()
except Exception as error:
    print('ERROR:', error)
else:
    print('Password entered:', password)

import platform

print(platform.system())
print(platform.release())

import platform

print(platform.python_version())
print(platform.python_build())

import platform

print(platform.machine())
print(platform.processor())

import threading

def print_numbers():
    for i in range(10):
        print(i)

def print_letters():
    for letter in 'abcdefghij':
        print(letter)

thread1 = threading.Thread(target=print_numbers)
thread2 = threading.Thread(target=print_letters)

thread1.start()
thread2.start()

import threading

lock = threading.Lock()

def print_numbers():
    lock.acquire()
    for i in range(10):
        print(i)
    lock.release()

def print_letters():
    lock.acquire()
    for letter in 'abcdefghij':
        print(letter)
    lock.release()

thread1 = threading.Thread(target=print_numbers)
thread2 = threading.Thread(target=print_letters)

thread1.start()
thread2.start()

import threading
import time

def slow_operation():
    time.sleep(5)  # これはIOバウンド操作です

thread1 = threading.Thread(target=slow_operation)
thread2 = threading.Thread(target=slow_operation)

thread1.start()
thread2.start()

from multiprocessing import Process

def print_numbers():
    for i in range(5):
        print('Number:', i)

def print_hello():
    for _ in range(5):
        print('Hello')

if __name__ == '__main__':
    process1 = Process(target=print_numbers)
    process2 = Process(target=print_hello)

    process1.start()
    process2.start()

    process1.join()
    process2.join()

from multiprocessing import Process, Value

def add_100(number):
    for _ in range(100):
        number.value += 1

if __name__ == '__main__':
    shared_number = Value('i', 0)

    process1 = Process(target=add_100, args=(shared_number,))
    process2 = Process(target=add_100, args=(shared_number,))

    process1.start()
    process2.start()

    process1.join()
    process2.join()

    print(shared_number.value)

from multiprocessing import Pool

def square(number):
    return number * number

if __name__ == '__main__':
    numbers = [1, 2, 3, 4, 5]

    with Pool() as p:
        results = p.map(square, numbers)
        print(results)

from concurrent.futures import ThreadPoolExecutor
import time

def task(message):
    time.sleep(2)
    return message

pool = ThreadPoolExecutor(max_workers=5)

future = pool.submit(task, ("Completed Task"))
print(future.result())

from concurrent.futures import ThreadPoolExecutor

def task(n):
    return n * 2

with ThreadPoolExecutor(max_workers=4) as executor:
    results = executor.map(task, [1, 2, 3, 4, 5])

for result in results:
    print(result)

from concurrent.futures import ProcessPoolExecutor

def task(n):
    return n * 2

with ProcessPoolExecutor(max_workers=4) as executor:
    results = executor.map(task, [1, 2, 3, 4, 5])

for result in results:
    print(result)

import subprocess

# UNIXコマンド'ls'を実行するための新しいプロセスを起動
process = subprocess.run(['ls'], stdout=subprocess.PIPE)

# 結果を表示
print(process.stdout.decode())

import subprocess

try:
    subprocess.run(['ls', 'non_existent_file'], check=True)
except subprocess.CalledProcessError:
    print("'ls'コマンドが失敗しました")

import subprocess

# 新しいプロセスを起動
process = subprocess.Popen(['grep', 'python'], stdin=subprocess.PIPE, stdout=subprocess.PIPE)

# プロセスに入力値を送る
stdout, _ = process.communicate(b'pythonたのしい\njavaもたのしい\n')

# 結果を出力
print(stdout.decode())

import queue

# 新しいキューを作成
q = queue.Queue()

# キューに要素を追加
q.put('apple')
q.put('banana')
q.put('cherry')

# キューから要素を削除
print(q.get())  # 'apple'
print(q.get())  # 'banana'

import queue

q = queue.Queue(2)  # サイズが2のキューを作成

print(q.empty())  # キューが空の場合はTrue

q.put('apple')
print(q.full())  # キューのサイズが満杯ではないのでFalse
q.put('banana')
print(q.full())  # キューのサイズが満杯なのでTrue

print(q.qsize())  # キューのサイズ確認

import queue
import threading

def producer(q):
    for i in range(5):
        q.put(i)
        print(f'Produced: {i}')

def consumer(q):
    while True:
        item = q.get()
        print(f'Consumed: {item}')
        q.task_done()

q = queue.Queue()

t1 = threading.Thread(target=producer, args=(q,))
t2 = threading.Thread(target=consumer, args=(q,))

t1.start()
t2.start()

q.join()  # すべてのタスク完了までブロックする

import asyncio

async def hello():
    print('Hello,')
    await asyncio.sleep(1)
    print('world!')

# イベントループを作成
loop = asyncio.get_event_loop()

# hello関数を2回並行実行
loop.run_until_complete(asyncio.gather(hello(), hello()))

# ループを閉じる
loop.close()

import asyncio

async def count():
    print("One")
    await asyncio.sleep(1)
    print("Two")

async def main():
    await asyncio.gather(count(), count(), count())

asyncio.run(main())

import asyncio

async def echo(reader, writer):
    data = await reader.read(100)
    message = data.decode()
    addr = writer.get_extra_info('peername')

    print(f"Received {message} from {addr}")

    print(f"Send: {message}")
    writer.write(data)
    await writer.drain()

    writer.close()

async def main():
    server = await asyncio.start_server(echo, '127.0.0.1', 8888)

    addr = server.sockets[0].getsockname()
    print(f'Serving on {addr}')

    async with server:
        await server.serve_forever()

asyncio.run(main())

import ssl
import socket

context = ssl.create_default_context()
with socket.create_connection(('www.python.org', 443)) as sock:
    with context.wrap_socket(sock, server_hostname='www.python.org') as ssock:
        print(ssock.version())

import ssl
import socket

context = ssl.SSLContext(ssl.PROTOCOL_TLSv1_2)
context.verify_mode = ssl.CERT_REQUIRED
context.load_verify_locations('ca_certs')

with socket.create_connection(('www.python.org', 443)) as sock:
    with context.wrap_socket(sock, server_hostname='www.python.org') as ssock:
        print(ssock.version())

import ssl
import urllib.request

context = ssl.SSLContext(ssl.PROTOCOL_TLSv1_2)
context.verify_mode = ssl.CERT_REQUIRED
context.load_verify_locations('ca_certs')

https_handler = urllib.request.HTTPSHandler(context=context)
opener = urllib.request.build_opener(https_handler)
urllib.request.install_opener(opener)

response = urllib.request.urlopen('https://www.python.org/')
print(response.read())

import signal
import time

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

signal.signal(signal.SIGINT, signal_handler)

while True:
    time.sleep(1)

import signal
import time

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

signal.signal(signal.SIGALRM, signal_handler)
signal.alarm(5)

while True:
    time.sleep(1)

import signal
import sys

def exit_gracefully(signum, frame):
    print("Exiting gracefully...")
    sys.exit(1)

signal.signal(signal.SIGINT, exit_gracefully)

while True:
    pass

import json

# Pythonの辞書型
data = {
  "name": "John",
  "age": 30,
  "city": "New York"
}

# JSONへ変換
json_data = json.dumps(data)
print(json_data)

import json

# Pythonの辞書型
data = {
  "name": "John",
  "age": 30,
  "city": "New York"
}

# JSONデータ書き込み
with open('data.json', 'w') as f:
    json.dump(data, f)

# JSONデータ読み込み
with open('data.json', 'r') as f:
    data = json.load(f)

print(data)

import json

# 複雑なオブジェクト
data = {
  "name": "Taro",
  "age": None,
  "married": True,
  "divorced": False,
  "children": ("Hanako", "Jiro"),
  "pets": None,
  "cars": [
    {"model": "Mazda", "mpg": 27.5},
    {"model": "Toyota", "mpg": 24.1}
  ]
}

# JSONへ変換
json_data = json.dumps(data)
print(json_data)