可迭代对象、迭代器、生成器之间的关系

from collections import Iterable,Iterator
from abc import ABCMeta, abstractmethod
assert 1 in [1,2,3]
# assert 4 in [1,2,3]
# assert len([1,2]) >=5,‘列表元素个数小于5‘

d = {1: ‘foo‘, 2: ‘bar‘, 3: ‘qux‘}
assert 1 in d
# assert ‘foo‘ in d

print(isinstance(iter([]),Iterable))#True
print(isinstance(iter([]),Iterator))#True
print(isinstance([],Iterable))#True

for i in iter([1,2,3]):
    print(‘111‘,i,type(i),type(iter([1,2,3])))
    ‘‘‘
    111 1 <class ‘int‘> <class ‘list_iterator‘>
    111 2 <class ‘int‘> <class ‘list_iterator‘>
    111 3 <class ‘int‘> <class ‘list_iterator‘>
    ‘‘‘

class Fib:
    def __init__(self):
        self.prev = 0
        self.curr = 1

    def __iter__(self):
        return self

    def __next__(self):
        value = self.curr
        self.curr += self.prev
        self.prev = value
        return value

f = Fib()

print(isinstance(f,Iterable))#True
print(isinstance(f,Iterator))#True