def test_filter_int_1():
assert utils.filter_int(2) == 2
def test_filter_int_5():
assert utils.filter_int([1, 2]) == ''
def test_filter_int_3():
assert utils.filter_int(set()) == ''
def test_filter_int_4():
assert utils.filter_int({}) == ''
def test_filter_int_2():
assert utils.filter_int('a') == ''
