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Why is creating a set from a filter much faster than creating a list or tuple?

Im works filteron interable and wants to keep the result in a sequence (I need a sequence so I can use random.choiceon it). I noticed that creating a collection from a filter object is much faster than creating a list or tuple. Why is this? First, I want the filter type to be a subtype of set, which would explain this, but the function filteris actually identical to the expression of the generator, so it cannot be truly internal.

I checked the following test to check the speed:

import time

def test ( n, seq ):
    for method in ( set, list, tuple ):
        t = time.time()
        for i in range( n ):
            method( seq )
        print( method.__name__, ( time.time() - t ) )

someFilter = filter( lambda x: x % 3 == 0, range( 1000 ) )
test( 10000000, someFilter )

And the results clearly talked about using the kit:

set 1.9240000247955322
list 8.82200002670288
tuple 7.031999826431274

, ? , , ? - ?

, range set list tuple ( ).

:

Svens , , :

import time

def testFilter ( n, test, rangeSize ):
    for method in ( set, list, tuple ):
        t = time.time()
        for i in range( n ):
            method( filter( test, range( rangeSize ) ) )
        print( method.__name__, ( time.time() - t ) )

testFilter( 100000, lambda x: x % 3 == 0, 1000 )

, , list tuple , set isnt , , :

set 27.868000030517578
list 27.131999969482422
tuple 27.138000011444092
+5
2

filter() Python 3, for. , , , , .

, , set() .

+11

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timeit, . , , .

, , ( , Python 3), ( method(iterator) ).

FWIW, pypy , .

[ , ]. ( ), - , , . , , ( , ).

+4

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