Python 명명 규칙에 대한 자세한 설명

BASE_DIR = os.path.dirname(os.path.dirname(os.path.abspath(file)))

SECRET_KEY = '(5hjjo=-=r1s43d+=yu(ay2vy_pe53ut0kzd5skzxa9@5#qf_x'
# SECURITY WARNING: don't run with debug turned on in production!
DEBUG = True
ALLOWED_HOSTS = []
# Application definition
INSTALLED_APPS = [
    'django.contrib.admin',
    'django.contrib.auth',
    'django.contrib.contenttypes',
    'django.contrib.sessions',
    'django.contrib.messages',
    'django.contrib.staticfiles',
    'helloapp',
]

OPTIONS={}
def register_option(name):
    return OPTIONS.setdefault(name,1<<len(OPTIONS))#bin(len(OPTIONS))查看二进制数据  
def has_option(options,name):
    return bool(options&name)
#定义标签  
BLUE=register_option(&#39;BLUE&#39;)
RED=register_option(&#39;RED&#39;)
YELLOW=register_option(&#39;YELLOW&#39;)
#设置标签  
SET=BLUE|RED
#判断标签是否存在设置中 
has_option(SET,BLUE)
has_option(SET,YELLOW)

class Base(object):
    def __secret(self):
        print("don't tell")
    def public(self):
        self.__secret()
class Top(Base):
    def __secret(self):
        print("never say never")
print(dir(Base))
b=Base()
b._Base__secret()
print(dir(Top))
Top().public()
#输出  
['_Base__secret',..., 'public']
don't tell
['_Base__secret', '_Top__secret', ..., 'public']
don't tell

def __init__(self):
    pass  
def __add__(self):
    pass