python classes

class A:
    def __init__(self, attr):
        self.attr = attr

a = A(5)
print(a.attr)
# 5

class A:
    common = 42
  
    def __init__(self, attr):
        self.attr = attr

a, b = A(5), A(6)
print(a.attr, b.attr)
# 5, 6

print(a.common, b.common)
# 42, 42

print(A.common)
# 42

# 0, 100, 100

class A:
    common = 42
  
    def __init__(self, attr):
        self.attr = attr

a.common = 0
print(a.common, b.common, A.common)

a, b = A(5), A(6)
A.common = 100
print(a.common, b.common, A.common)

# 100, 100, 100

print(b.__dict__)

{'attr': 6}

print(a.__dict__)

{'attr': 5, 'common': 0}

for k, v in A.__dict__.items():
    print(k, v)

__module__ __main__
common 100
__init__ <function A.__init__ at 0x7fa8a8c4fd30>
__dict__ <attribute '__dict__' of 'A' objects>
__weakref__ <attribute '__weakref__' of 'A' objects>
__doc__ None

# ищем 'attr' в __dict__ инстанса `a`
# ищем 'attr' в __dict__ класса `А`

class A:
    def __init__(self, attr):
        self.attr = attr


a = A(5)
print(a.attr)

Traceback (most recent call last):
...
AttributeError: 'A' object has no attribute 'lol'

class A:
    pass


print(A().lol)

class A:
    pass


a = A()
print(a.__dict__)
# {}

print(a.lol)

# 42

print(a.__dict__)

{'lol': 42}

a.lol = 42

class A:
    common = []


a, b = A(), A()
print(a.common, b.common, A.common)
# [], [], []

a.common.append('kek')
print(a.common, b.common, A.common)

# ['kek'] ['kek'] ['kek']

class Student:
    def __init__(self):
        self.failed_tests = []
        self.is_active = True

s = Student()
s.failed_tests.append('ИН ЯЗ')
s.failed_tests.append('ООП')
print(s.is_active)  # True

s.failed_tests.append('Сети')
print(s.is_active)  # True

class Student:
    def __init__(self):
        self.failed_tests = []
        self.is_active = True

    def add_failed_test(self, test):
        self.failed_tests.append(test)
        if len(self.failed_tests) >= 3:
            self.is_active = False

class Student:
    EXPEL_THRESHOLD = 3

    def __init__(self):
        self._failed_tests = []
        self.is_active = True

    def add_failed_test(self, test):
        self._failed_tests.append(test)
        if len(self._failed_tests) >= self.EXPEL_THRESHOLD:
            self.is_active = False

s = Student()
s.add_failed_test('ИН ЯЗ')
s.add_failed_test('ООП')
print(s.is_active)  # True
s.add_failed_test('Сети')
print(s.is_active)  # False

while True:
    try:
        log_line = input()
    except EOFError:
        break
    if not log_line:
        break

    ...  # обрабатываем строку лога

05 python classes

By persi

python classes

05 python classes

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