def f1(seq):
seen = set()
return [ x for x in seq if x not in seen and not seen.add(x)]
def f7(seq):
seen = set()
seen_add = seen.add
return [ x for x in seq if x not in seen and not seen_add(x)]
import dis
print "f1"
dis.dis(f1)
print "f7"
dis.dis(f7)
ZGVmIGYxKHNlcSk6CiAgICBzZWVuID0gc2V0KCkKICAgIHJldHVybiBbIHggZm9yIHggaW4gc2VxIGlmIHggbm90IGluIHNlZW4gYW5kIG5vdCBzZWVuLmFkZCh4KV0KICAgIApkZWYgZjcoc2VxKToKICAgIHNlZW4gPSBzZXQoKQogICAgc2Vlbl9hZGQgPSBzZWVuLmFkZAogICAgcmV0dXJuIFsgeCBmb3IgeCBpbiBzZXEgaWYgeCBub3QgaW4gc2VlbiBhbmQgbm90IHNlZW5fYWRkKHgpXQogICAgCmltcG9ydCBkaXMKcHJpbnQgImYxIgpkaXMuZGlzKGYxKQoKcHJpbnQgImY3IgpkaXMuZGlzKGY3KQ==