ZhouYang1993

class Student:
    def __init__(self):
        self._score = 0

    @property
    def score(self):
        return self._score

    @score.setter
    def score(self, s):

ZhouYang1993

class C(object):

    @property
    def x(self):
        return self._x

    @x.setter
    def x(self, value):
        self._x = value

ZhouYang1993

class Student:
    def __init__(self):
        self._score = 0

    def score(self):
        return self._score

    def set_score(self, s):
        if 0 <= s <= 100:
            self._score = s

ZhouYang1993

class Student:
    def __init__(self):
        self._score = 0

    @property
    def score(self):
        return self._score

    @score.deleter
    def score(self):

ZhouYang1993

A = [1, 2, 3]
B = A
B.append(4)
print(A)
# [1, 2, 3, 4]
print(B)
# [1, 2, 3, 4]

ZhouYang1993

import copy

A = [1, 2, 3]
# B = A.copy()
B = copy.copy(A)  # The same as `B = A.copy()`
B.append(4)

print(A)
# [1, 2, 3]

ZhouYang1993

import copy

A = [[1, 2], ['a', 'b']]
B = copy.copy(A)  # The same as `B = A.copy()`
B.append(4)
print(A)
# [[1, 2], ['a', 'b']]
print(B)
# [[1, 2], ['a', 'b'], 4]

ZhouYang1993

import copy

A = [[1, 2], ['a', 'b']]
B = copy.deepcopy(A)

B.append(4)
print(A)
# [[1, 2], ['a', 'b']]
print(B)
# [[1, 2], ['a', 'b'], 4]

ZhouYang1993

def f(x):
    return x * x
r = map(f, [1, 2, 3, 4, 5, 6, 7, 8, 9])
print(list(r))
# [1, 4, 9, 16, 25, 36, 49, 64, 81]

ZhouYang1993

from functools import reduce

city = ['L', 'o', 'n', 'd', 'o', 'n', 2, 0, 2, 0]
city_to_str = reduce(lambda x, y: str(x) + str(y), city)
print(city_to_str)
# London2020