python中filter与map不同

list = map(func, iter)

from collections import Iterable

lst = [1, 2, 5, 6, 7]

res = filter(lambda x: x % 2 == 0, lst)

# res 是一个可迭代对象

print(isinstance(res, Iterable), type(res))

for item in res:

print(item)

def only_int(x):

    try:

        if isinstance(x, int):

            return True

        else:

            return False

    except ValueError as e:

        return False

dt = filter(type_int,[1,2,3,3,'3232',-34.5,34.5])

>>> list(dt)

[1, 2, 3, 3]