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NT bidding revisited


Winstonm

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jdonn, you can evaluate the hand to 6 hcp, but that seems overly pessimistic because pard has a moderately strong hand. That strength increases the chance of pard being able to make use of your poorly-positioned assets. To devaluate 2 hcp on this hand and sign-off borders on weak-hand-masterminding and is bound to lead to some bad scores in the long run. You can't afford that at imps, unless you need a swing.

Well I'm assuming you are partner, so even after I sign off you will bid game for me anyway since that's your favorite thing to do when you are limited and not the captain. I expect 1NT p 2 p 3NT, making the whole issue moot.

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DealMaster Analysis: When opener has 2 spades, 3N makes 33% of the time and 5D makes 18%. When opener has 3+ spades, 4S makes 58% of the time.

 

So mentioning diam to get to a futile 5D contract is a loser.

I don't understand this conclusion at all.

 

If you decide the hand is worth a game force, then surely it's right to bid diamonds?

 

You don't say how many of the 18% of the time 5D makes 3NT also makes, but if mentioning diamonds lets us get to 5D making instead of 3NT going off, say 10% of the time, then why not do so? Partner also knows that 5D needs 11 tricks. You can argue that they might lead diamonds if we don't bid them, but that seems not very likely with KJxxx.

 

As a slight side point, I think that hands with a source of tricks (either in the the 1NT bidder's hand or as responder) make 3NT more often single dummy than they should do, because the choice of opening lead becomes critical.

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:P Transferring to spades, then bidding 2NT is a winner by a mile based on my simulation of 50 hands using Pavlicek's hand generator*. Using this method I created a statistically unbiased data base of the opening notrumper's possible hands and then used my own bidding and play analysis to evaluate the results.

 

Game was reached 28 times out of 50 hands. Seventeen of these were high percentage games (3-2 suit splits or better). Five more were worth bidding (50% plus or minus a little). Only six were anti-percentage games, but even these had some play. When game was not bid, the resulting part-score contracts all had excellent prospects. In addition, we missed four high percentage games and four marginal games. The high percentage games missed had some common characteristics. The opening notrumper held a 15 HCP hand with three spades to an honor and prime cards (aces and supported kings) in the side suits.

 

By comparison, transferring, then raising a 3 super acceptance to four only happened six times (12% of the time). All six cases were virtual lay downs for 4. Unhappily, this method missed eleven high percentage games (and five more 50%+ or - games), playing them in 2 instead. In all of the six cases where opening notrumper gave a superacceptance, 4 was an excellent contract even if responder held a small club in place of the king. Finally, I noted that superaccepting with only three trumps and 17 HCP or four trumps and 15 HCP was a bit too pushy, leading to low percentage contracts.

 

In summary, standard hand evaluation methods worked much better than relying on the newfangled 'super acceptance' method alone. I got the feeling working through the 50 hands that it was the presence of the stiff club king that caused the traditional method to work so well. Using both tools, one can reach good games whether or not their hand has one small club or the singleton king.

 

*I allowed 5-4-2-2 hands to open 1NT, IF they had a rebid problem over a 1 response, and I excluded balanced six baggers.

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Hrm, I will try my own sim. I could certainly be talked into inviting, in fact in my very first post that's what I did at imps anyway. I have serious doubts I could be talked into bidding game.

 

To be edited...

 

(later) I ignored hands that superaccept, since then it doesn't matter what your original intentions were. I was extremely fair in both the bidding, play, and opening lead, but I was very formulaic in opener's actions over the invitation. That was by design so I wouldn't have to make biased judgment calls. So with 16 or 17 opener always accepted, or with 15 and four card support. And opener always prefered spades to notrump with three of them.

 

I did generation of all four hands, so some good games went down, a couple bad games made, etc etc, just like would happen at the table. I always made a realistic lead, even to the detriment of the defense (once a low diamond from QT9xx, once a club from AQJTx, etc). So for example, that explains hands 7-8-9, all of which would have had very different results with the defenders' hands switched.

 

I included partner's 1NT bid in every case.

 

1) 3NT -2, A9 AQT8 973 AQ95

2) 4S =, AKT9 A93 AT9 J94

3) 2NT +1, QT AT2 A73 AJ975

4) 3NT -1, Q4 KQ43 AQ A9842

5) 3NT -1, K6 AKQ7 Q4 QT875

6) 2NT -2, Q3 AJ3 A73 A9863

7) 2NT -6, AK Q84 AQT94 832

8) 4S -1, KT9 AQ9 96 AQJ83

9) 3NT =, AT KJ94 A64 A532

10) 4S =, AT6 AT9 A73 AT54

11) 4S =, KT94 AQ2 Q97 A64

12) 4S +1, KQT KJT7 A6 A972

13) 2NT =, AQ K974 AQ7 9532

14) 3NT +1, A4 QJ93 AT96 AQ5

15) 3NT -1, A6 AJ32 Q7 AQJ65

16) 4S +1, K63 AK7 Q97 A654

17) 2NT =, K9 AT42 AT4 AT43

18) 4S -1, AK3 A9 A64 JT742

19) 3NT -2, K3 QJ AQ763 AT64

20) 4S =, AK96 AQ8 Q76 T82

21) 4S =, AT6 A3 AQ93 Q876

22) 4S =, AKT6 T43 QT AQJ6

23) 3S +1, KT3 KT7 A3 AJT98

24) 2NT -2, A4 AKT2 AT43 743

25) 2NT =, Q4 AK2 AT97 Q762

 

Totals: 2NT seven times, -6 once, -2 twice, = thrice, +1 once. 3S once, +1 (but partner would actually have accepted so I'll count it as 4 =). 3NT seven times, -2 twice, -1 thrice, = once, +1 once. 4 eleven times, -1 twice, = seven times, +1 twice.

 

Conclusions: Better to invite than signoff at imps, though not by a mile. It got to game 18 times, making 11 of them. At matchpoints, still correct to invite based on this little study, but the sample size is too small to draw a matchpoint conclusion since about three hands going the other way would have swayed it.

 

Signing off was not quite enough. However, blasting game was also far too much. Game made 11/18 times partner would accept, 1/7 times partner would reject, so clearly lost over inviting.

 

Two side conclusions:

- When partner transfers and invites, accept with four card support no matter how terrible your hand is, even 15 with 4333. I have actually seen this work badly in person once that I recall, but it went 2 for 2 here (hands 11 and 20).

- Play 2 then 2 as a light unbalanced invite, it has a huge advantage on this kind of hand. You get to the making games, and also do much better in partscores as partner can play in your second suit if he chooses. I would guess this is far more valuable than other uses for the bid. You can see that 2NT did quite terribly, and almost always either 2 or 3 would have done better.

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What are honors worth?

 

Their values comes from a few factors:

 

a. Tricks. An ace is a trick no matter how you slice it.

 

b. Promotional value. When you have an honor, it immediately raises the rank of all the other honors in both hands. E.G. If you have the ace of spades, then the K of spades becomes like an ace. If you have the K then the QJT becomes like the KQJ. Note: promotional value is value on power. You lead your K forcing out the A, and then your Q becomes good.

 

c. Positional value.

If you don't have the ace, but you lead toward the Kx it will score half the time.

Having honors in combination (in the same hand) greatly improves their positional value. KQx vs xxx will take 2 tricks half the time (assuming enough entries) while Kxx vs Qxx will take 2 tricks only when the ace is singleton or doubleton and you guess who has it. You take a lot less tricks on average with this holding.

 

d. entries/communication. Being able to get from hand to hand without wasting tricks is valuable. If you can't get to the correct hand, the positional value of your holdings goes down and possibly the promotional value as well. For instance:

Picture K vs AQJx vs Kx vs AQJx. If in the first case you need to overtake the K, you have used the K to promote the QJ but have lost the trick taking value of the K.

 

e. timing and control. While KQJT are 3 tricks after you knock out the ace, this holding is still worse than the AKQ since you have to lose a tempo to set up your 3 tricks. If you have to give up the lead, the opps may be able to set up tricks of their own before you cash yours.

 

WHat is the value of a stiff K relative to Kx or K and more length?

 

1. is the almost the same. Its worth a trick whenever partner has the A (except when its a stiff A).

 

2. the promotional value is almost the same as the K with length but if partner has the stiff Q or the AQ it loses its promotional value.

 

3. this value is completely lost

 

4. this value is greatly reduced since you do not have 2 way communication, and if partner doesn't have the ace, you do not have an entry (while Kx is an entry 50% of the time) and you might have to give up the trick taking value (value 1) in order to use the K to get to partner's hand

 

5. this value is greatly reduced since you do not have either absolute control (and A or a KQ) or positional control (protected K)

 

Now what is Jxxxx worth?

It has very little value in all 5 measures. Its trick taking value depends on the probability that partner has enough of the higher honors... Since there are no good spots, it has little promotional value....

etc.

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:D My head is still aching from trying to rapidly evaluate fifty bridge hands as to how many tricks are available at what odds for each hand. I may have made some mistakes. I do not think I erred in constructing a good random sample, though. The trick here is to use Pavlicek's hand generator to generate a random sample based on criteria looser than necessary but that covers all possible cases. Next, I cull out any hands in this group that would not open 1NT by using my special program Eyeballs 1.0.

 

The hands generated for the opening notrumper are shown below. The first 50 have been culled using Eyeballs 1.0 and were the basis for my aforementioned analysis. The suits are spades, hearts, diamonds, clubs

 

AQ4 KQ87 T64 A43 1

AQ4 A743 AT6 Q94 2

AQ64 AQ2 A4 J876 3

AQ9 Q843 AQT7 JT 4

AQ96 K973 A9 A84 5

AQT A94 Q6 QJ763 6

AT KQJT T9 AJ754 7

AT QJT2 QT4 AQJ5 8

AT AQ4 A73 QJT93 9

AT4 K2 AQT96 QJ9 10

AT9 AQ83 AT96 Q8 11

K3 AQ4 AQ4 QT962 12

K43 AK3 AQ97 J96 13

K64 K973 A4 AQJT 14

K9 AQ4 AT96 AT74 15

KQ QT87 AQT73 QJ 16

KQ43 AJ82 QT QJ9 17

KQ9 K742 AT6 A42 18

KQT AK84 A64 942 19

KQT4 T942 AQ6 AQ 20

KT AQT3 AQT74 64 21

KT9 AKJ2 Q6 Q854 22

Q3 AQ7 A964 A754 23

Q4 AKQJ 43 AJ762 24

Q6 AJ7 AT63 AQ83 25

Q63 A942 A9 AJT5 26

Q9643 AQJ AQ4 Q3 27

QT6 AKQ AT J8642 28

T63 AK84 A7 AJ63 29

AT63 42 AQ94 AJ6 30

AT96 QJ Q94 AQ62 31

K3 AQ7 AQ7 T9872 32

K43 AQ7 AQ6 Q963 33

K643 A8 Q63 AQ72 34

K94 AK82 Q3 A872 35

KQ AJ73 A643 QT2 36

KQ6 KT9 T4 AQJT5 37

KQ9 T942 AQT A82 38

KQT KJ8 QT AJT98 39

KQT4 AJ7 43 AQ53 40

KT AJ87 Q63 AQJ2 41

KT9 AQ94 A7 QT83 42

Q3 AK9 QT4 AJ952 43

Q4 AQ4 QT764 AQ9 44

Q64 AJ32 A76 A54 45

QT KJ98 QT AQJT3 46

QT63 KQT8 AQ A85 47

T64 AK74 AQ97 A3 48

93 AKQ Q43 A9632 49

643 AK82 A96 AT3 50

A4 AJ97 QT9 A632 51

A6 K94 AT64 A832 52

A6 KT72 A43 AT82 53

A63 AQJ7 A93 J42 54

A64 AJ7 QT4 A987 55

A93 A73 AQ JT954 56

A94 KQ9 Q764 A98 57

A963 AK7 AQ7 432 58

AK AK97 Q3 JT953 59

AK4 Q73 AQ763 82 60

AK43 T83 AT AQ87 61

AK6 Q98 63 AQJ76 62

AK94 AQ7 A976 72 63

AKQ3 KT92 97 A32 64

AKQ6 QT8 AQT T97 65

AKQT A8 AT6 T632 66

AKT 983 AQ64 Q96 67

AQ AK42 A9763 74 68

AQ KQJ8 AT JT864 69

AQ3 AJ7 743 AT64 70

AQ4 93 AQ76 A652 71

AQ4 74 AQ93 QJ82 72

AQ9 AQJ8 Q974 92 73

AQ9 A97 A9743 Q4 74

AQ96 A42 A964 JT 75

AQT4 K74 QT9 A95 76

AT AQ72 QT3 AJT2 77

AT AT98 AQ J7654 78

AT KQJ AQ93 T962 79

AT6 AJ97 AT76 A3 80

AT63 KJ98 Q3 AQ5 81

K3 AKJ T97 AT964 82

K4 T93 AQ93 AQJ6 83

K6 AKJ7 T4 A9653 84

K9 AQJT Q6 AJ652 85

KQ K74 A943 AJ86 86

KQ A97 AQ93 QT74 87

KQ6 QT92 AQ Q953 88

KQ9 KT82 A4 QJ32 89

KQT AJ9 AQ4 T863 90

KQT4 AT2 AT9 Q62 91

KT3 94 AQ74 AQ92 92

KT96 83 AQT AQJ8 93

Q4 AKQ9 QT97 A53 94

Q4 AK98 T6 AQJ52 95

Q6 AKJ2 A63 J543 96

Q93 KJ7 AQ QJ532 97

QT AQT8 64 AQJT6 98

QT9 A84 AT93 AQ2 99

T9 AKQJ T64 AQ74 100

94 AQ73 Q3 AQJT4 101

963 AQJ2 AT3 AT2 102

A4 QT87 A74 AJ64 103

A6 K874 A93 AJ84 104

A6 AK97 A96 J976 105

A63 AK3 A64 J932 106

A9 QJ74 AT74 A98 107

A93 AK94 A3 QT98 108

A94 Q3 AQ43 QJT3 109

A963 AK AQT4 962 110

AK QJ74 Q96 QJ63 111

AK4 Q84 AT64 A92 112

AK6 AQT9 QT64 53 113

AK6 AQT9 76 AT98 114

AK94 Q84 QT A984 115

AKQ3 A32 Q6 T542 116

AKQ9 KQ4 943 Q65 117

AKT QT7 Q6 AJ952 118

AQ K942 QT4 A963 119

AQ KQ82 QT9 QT93 120

AQ3 KQ93 AT4 Q95 121

AQ4 KJT7 76 AJ87 122

AQ6 A93 94 AJ874 123

AQ9 AJ74 AQ 9543 124

AQ9 AQT2 A9 T963 125

AQ96 KQ2 AT43 T5 126

AQT6 KT2 93 AQ73 127

AT A94 A94 AJT94 128

AT AQ42 AQT9 J97 129

AT3 AQJ T3 AJ942 130

AT6 KJ7 A974 A74 131

AT64 AKJ 43 AJ42 132

K3 AQ AQ43 J9854 133

K43 AQ AQ64 9865 134

K63 QJ8 A63 AQ62 135

K9 AK7 963 AJ653 136

KQ QJ92 AQT6 J62 137

KQ3 QT AQT4 QJ43 138

KQ9 AQ4 A3 87532 139

KQ96 T82 A43 AQ8 140

KQT4 A9 Q763 A76 141

KQT9 J9 AQ93 A83 142

KT4 K72 A4 AJT84 143

Q3 AK4 AQ93 9764 144

Q4 AQ82 AT6 A532 145

Q4 AKQ3 AT6 J432 146

Q6 KQJ9 AQ7 QJ72 147

Q96 KJ AQ93 A654 148

QT QJ94 AQ9 AT92 149

QT96 AQ AQ6 JT65 150

96 AJ2 A76 AQT98 151

A3 K94 AT4 AJ963 152

A43 KQ7 Q6 AT872 153

A63 AQJT 64 A985 154

A64 KQJ4 QT3 A53 155

A93 QJ4 A964 A54 156

A94 AKJ8 63 A942 157

A96 AJT3 AQ7 J63 158

AK QJ72 A9 J7542 159

AK3 AQ98 AT96 95 160

AK6 A984 Q64 A72 161

AK93 KQT Q9 JT98 162

AKQ Q7 AQ4 87543 163

AKQT AQ T743 QT3 164

AKT AKQT 97 J987 165

AKT9 T9 A3 AT932 166

AQ K32 AT3 AT964 167

AQ3 KJ72 97 AJ42 168

T93 AQJ2 Q6 AQ63 169

96 AQ72 A973 AJ9 170

964 AKQ9 A9 QT84 171

A43 AQT Q7 AT654 172

A6 AT94 T6 AQJ72 173

A6 AK98 Q76 Q974 174

A63 KT97 AQ9 Q62 175

A9 KQJ A73 QJ653 176

A94 AT A63 A7532 177

A94 AQ97 AQ9 T92 178

AK T983 A6 A5432 179

AK AK97 Q63 T732 180

AK4 AK7 43 J9876 181

AK6 KT74 AQT 874 182

AK64 AT7 T3 A854 183

AK94 74 AQ64 QT9 184

AKQ4 942 AQ9 T72 185

AKQT A94 A9 8754 186

AKT KJ2 74 AJ986 187

AKT9 A874 A6 873 188

AQ QJ83 Q3 AT632 189

AQ AK73 QT3 T852 190

AQ4 AK93 AT63 43 191

AQ4 AQ2 A3 J9752 192

AQ6 J98 AQ9 Q652 193

AQ9 A72 64 AQ653 194

AQ94 AKT8 94 A32 195

AQT AJ A9743 J72 196

AQT6 KT A643 AT5 197

AT KJ4 QT63 AQ82 198

AT KJT A973 QJT9 199

AT4 AQ74 AQ7 975 200

AT6 A7 QT3 AJ976 201

 

If you want to analyze them, be my guest. It took me a couple of hours to do 50 and then write up the results. Working through the sample is a very good way to get a feel for what is right and/or wrong with each bidding approach. I did not evaluate the game forcing sequence that Xfers to spades and then bids 3. It seemed almost self-evident that it led to too many instances of overbidding. My main feeling doing this was admiration for how well our traditional bidding system works.

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Without going through a full analysis (not that much free time on my hands) I did notice that 4 is excellent opposite all the openers which include four-card spades. This seems to vindicate the "bid stayman" approach to some degree. At least it seems clear that "bid stayman and raise to game if partner has spades" is better than "transfer and pass unless super-accept."
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Although not in the original list of options, in my methods I would respond 2D showing either a GF hand with more than 3 Spades (unbalanced) or a weaker hand (potentially very weak) with more than 4 Spades. Opener commits beyond 2S with more than 3 Spades, upon which as responder I commit to game. With fewer than 4 Spades opener distinguishes min v max according to 2H/2S rebid. If max I commit to game (3N opposite doubleton Spade, 4S opposite 3). If min I stop in 2S. I might miss the odd game but hope to gain on corresponding hands where 2S is the limit.
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I would transfer then pass unless superaccepted at any scoring. This is not pessimistic, it's realistic.

 

You have another way to win, you see. It may not be the end of it, someone might come with a Dbl or bid 3C, in which case I can wheel out a non-forcing 3D.

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Glen Ashton, a frequent contributor here and the author of the ETM victory system, has written up his adaptation of inverted stayman for handling hands like this. You can find his right up at http://www.bridgematters.com/etmnt06.pdf

 

Let me quote a piece of what Glen says about inverted stayman in this document.

Almost all game invite hands make use of Inverted Stayman, a brilliant invention of the Bridge World’s Jeff Rubens. ETM decided to use this when our independent analysis determined that an invite hand with five of a major is better bid using 2♣ then a transfer.

 

Basically, he would start responders hand with 2, which allows him to make a game invite and stay at 2 or stop in 3. To illustrate his method, I took the first 10 hands from the list of jdeegan to illustrate the method.

 

♠ J8752

♥ 65

KJ852

♣ K

 

AQ4 KQ87 T64 A43 1

 

1NT - 2C

2S! - Pass or 3

 

Where 2 shows 4 or 5 's and a minimum hand. Pass and 3 are both to play.

 

AQ4 A743 AT6 Q94 2

 

1NT - 2

2 - 2

3 - 3NT

4

 

Where 2 is ANY MAXIMUM, or a minimum with no four card major,

2 is invitational with 5 or constructive with 5 and 4+

3 game invite values in both minors, maximum, and 4/5 's

 

AQ64 AQ2 A4 J876 3

 

1NT - 2

2 - 2

4

 

AQ9 Q843 AQT7 JT 4

 

1NT - 2

2 - pass or 3, see hand 1

 

AQ96 K973 A9 A84 5

 

1NT - 2

3NT - 4

4

 

Where 3NT is maximum, 4-4 in majors, likes both minors

4 is transfer to 4

 

AQT A94 Q6 QJ763 6

 

1NT - 2

2 - 2

3 - 4

 

3 = game try, values for both minors

 

AT KQJT T9 AJ754 7

 

1NT - 2

2 - pass

 

 

AT QJT2 QT4 AQJ5 8

 

1NT - 2

2 - 3

3NT - Pass

 

3 = maximum, 4/5 values in both minors,

 

AT AQ4 A73 QJT93 9

 

1NT - 2

2 - 2NT

3NT - Pass

 

2NT = maximum, less than 4/5 , game try.

 

AT4 K2 AQT96 QJ9 10

 

1NT - 2

2 - 2

3 - 4

 

Ok, overbid this one :-)

 

Anyway, for anyone thinking about these issues, take a look at Glen's pdf at the link above. I don't play these methods (yet, hehehe), but they do look interesting (as does almost everything else on his bridgematters website).

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Not yet had a chance to look at these in depth, and note to self to do so, but in the meantime:

 

♠  J8752 

♥  65 

KJ852 

♣  K

 

AQ4 KQ87 T64 A43 1

 

1NT - 2C

2S! - Pass or 3

 

Where 2 shows 4 or 5 's and a minimum hand. Pass and 3 are both to play.

So, at this stage, opener could have 4 card Spade support and minimum? Not sure I like that.

 

 

AQ4 A743 AT6 Q94 2

 

1NT - 2

2 - 2

3 - 3NT

4

 

Where 2 is ANY MAXIMUM, or a minimum with no four card major,

 

Contrast with:

 

AQ96 K973 A9 A84 5

 

1NT - 2

3NT - 4

4

 

Where 3NT is maximum, 4-4 in majors, likes both minors

 

So 2D is not "ANY MAXIMUM"?

 

Guess I will have to look at the detailed notes.

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Not yet had a chance to look at these in depth, and note to self to do so, but in the meantime:

 

♠  J8752 

♥  65 

KJ852 

♣  K

 

AQ4 KQ87 T64 A43 1

 

1NT - 2C

2S! - Pass or 3

 

Where 2 shows 4 or 5 's and a minimum hand. Pass and 3 are both to play.

So, at this stage, opener could have 4 card Spade support and minimum? Not sure I like that.

 

No, opener can not have 4 when he bids 2. In addition to promising hearts, 2 denies both maximum and 4 's.

 

 

AQ4 A743 AT6 Q94 2

 

1NT - 2

2 - 2

3 - 3NT

4

 

Where 2 is ANY MAXIMUM, or a minimum with no four card major,

 

Contrast with:

 

AQ96 K973 A9 A84 5

 

1NT - 2

3NT - 4

4

 

Where 3NT is maximum, 4-4 in majors, likes both minors

 

So 2D is not "ANY MAXIMUM"? (any maximum except 4-4 in the majors, obviously.. This is not my method. I just returned to it when this discussion started.

Guess I will have to look at the detailed notes.

 

Me too.. I just shared this link because it seemed relevant to the discussion of this hand.

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