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Theorem paste 15893
Description: Pasting lemma. If A and B are closed sets in X with A u. B = X, then any function whose restrictions to A and B are continuous is continuous on all of X.
Hypotheses
Ref Expression
paste.1 |- X = U.J
paste.2 |- Y = U.K
Assertion
Ref Expression
paste |- (((J e. Top /\ K e. Top) /\ (A e. (Clsd` J) /\ B e. (Clsd` J) /\ (A u. B) = X) /\ (F:X-->Y /\ (F |` A) e. ((subSp` <.A, J>.) Cn K) /\ (F |` B) e. ((subSp` <.B, J>.) Cn K))) -> F e. (J Cn K))

Proof of Theorem paste
StepHypRef Expression
1 paste.1 . . . 4 |- X = U.J
2 paste.2 . . . 4 |- Y = U.K
31, 2iscncl 9047 . . 3 |- ((J e. Top /\ K e. Top) -> (F e. (J Cn K) <-> (F:X-->Y /\ A.y e. (Clsd` K)(`'F"y) e. (Clsd` J))))
433ad2ant1 897 . 2 |- (((J e. Top /\ K e. Top) /\ (A e. (Clsd` J) /\ B e. (Clsd` J) /\ (A u. B) = X) /\ (F:X-->Y /\ (F |` A) e. ((subSp` <.A, J>.) Cn K) /\ (F |` B) e. ((subSp` <.B, J>.) Cn K))) -> (F e. (J Cn K) <-> (F:X-->Y /\ A.y e. (Clsd` K)(`'F"y) e. (Clsd` J))))
5 simp1 876 . . 3 |- ((F:X-->Y /\ (F |` A) e. ((subSp` <.A, J>.) Cn K) /\ (F |` B) e. ((subSp` <.B, J>.) Cn K)) -> F:X-->Y)
653ad2ant3 899 . 2 |- (((J e. Top /\ K e. Top) /\ (A e. (Clsd` J) /\ B e. (Clsd` J) /\ (A u. B) = X) /\ (F:X-->Y /\ (F |` A) e. ((subSp` <.A, J>.) Cn K) /\ (F |` B) e. ((subSp` <.B, J>.) Cn K))) -> F:X-->Y)
7 imassrn 4278 . . . . . . . . . . . . 13 |- (`'F"y) C_ ran `' F
87a1i 8 . . . . . . . . . . . 12 |- (F:X-->Y -> (`'F"y) C_ ran `' F)
9 fdm 4567 . . . . . . . . . . . . 13 |- (F:X-->Y -> dom F = X)
10 dfdm4 4151 . . . . . . . . . . . . 13 |- dom F = ran `' F
119, 10syl5eqr 1942 . . . . . . . . . . . 12 |- (F:X-->Y -> ran `' F = X)
128, 11sseqtrd 2653 . . . . . . . . . . 11 |- (F:X-->Y -> (`'F"y) C_ X)
13 df-ss 2605 . . . . . . . . . . . . 13 |- ((`'F"y) C_ X <-> ((`'F"y) i^i X) = (`'F"y))
1413biimpi 168 . . . . . . . . . . . 12 |- ((`'F"y) C_ X -> ((`'F"y) i^i X) = (`'F"y))
1514eqcomd 1889 . . . . . . . . . . 11 |- ((`'F"y) C_ X -> (`'F"y) = ((`'F"y) i^i X))
1612, 15syl 12 . . . . . . . . . 10 |- (F:X-->Y -> (`'F"y) = ((`'F"y) i^i X))
1716adantl 424 . . . . . . . . 9 |- (((A u. B) = X /\ F:X-->Y) -> (`'F"y) = ((`'F"y) i^i X))
18 ineq2 2790 . . . . . . . . . . 11 |- (X = (A u. B) -> ((`'F"y) i^i X) = ((`'F"y) i^i (A u. B)))
1918eqcoms 1887 . . . . . . . . . 10 |- ((A u. B) = X -> ((`'F"y) i^i X) = ((`'F"y) i^i (A u. B)))
2019adantr 425 . . . . . . . . 9 |- (((A u. B) = X /\ F:X-->Y) -> ((`'F"y) i^i X) = ((`'F"y) i^i (A u. B)))
21 ffun 4565 . . . . . . . . . . . 12 |- (F:X-->Y -> Fun F)
22 respreima 15684 . . . . . . . . . . . . 13 |- (Fun F -> (`'(F |` A)"y) = ((`'F"y) i^i A))
23 respreima 15684 . . . . . . . . . . . . 13 |- (Fun F -> (`'(F |` B)"y) = ((`'F"y) i^i B))
2422, 23uneq12d 2756 . . . . . . . . . . . 12 |- (Fun F -> ((`'(F |` A)"y) u. (`'(F |` B)"y)) = (((`'F"y) i^i A) u. ((`'F"y) i^i B)))
2521, 24syl 12 . . . . . . . . . . 11 |- (F:X-->Y -> ((`'(F |` A)"y) u. (`'(F |` B)"y)) = (((`'F"y) i^i A) u. ((`'F"y) i^i B)))
26 indi 2838 . . . . . . . . . . 11 |- ((`'F"y) i^i (A u. B)) = (((`'F"y) i^i A) u. ((`'F"y) i^i B))
2725, 26syl6reqr 1947 . . . . . . . . . 10 |- (F:X-->Y -> ((`'F"y) i^i (A u. B)) = ((`'(F |` A)"y) u. (`'(F |` B)"y)))
2827adantl 424 . . . . . . . . 9 |- (((A u. B) = X /\ F:X-->Y) -> ((`'F"y) i^i (A u. B)) = ((`'(F |` A)"y) u. (`'(F |` B)"y)))
2917, 20, 283eqtrd 1929 . . . . . . . 8 |- (((A u. B) = X /\ F:X-->Y) -> (`'F"y) = ((`'(F |` A)"y) u. (`'(F |` B)"y)))
30293ad2antr1 1041 . . . . . . 7 |- (((A u. B) = X /\ (F:X-->Y /\ (F |` A) e. ((subSp` <.A, J>.) Cn K) /\ (F |` B) e. ((subSp` <.B, J>.) Cn K))) -> (`'F"y) = ((`'(F |` A)"y) u. (`'(F |` B)"y)))
31303ad2antl3 1040 . . . . . 6 |- (((A e. (Clsd` J) /\ B e. (Clsd` J) /\ (A u. B) = X) /\ (F:X-->Y /\ (F |` A) e. ((subSp` <.A, J>.) Cn K) /\ (F |` B) e. ((subSp` <.B, J>.) Cn K))) -> (`'F"y) = ((`'(F |` A)"y) u. (`'(F |` B)"y)))
32313adant1 894 . . . . 5 |- (((J e. Top /\ K e. Top) /\ (A e. (Clsd` J) /\ B e. (Clsd` J) /\ (A u. B) = X) /\ (F:X-->Y /\ (F |` A) e. ((subSp` <.A, J>.) Cn K) /\ (F |` B) e. ((subSp` <.B, J>.) Cn K))) -> (`'F"y) = ((`'(F |` A)"y) u. (`'(F |` B)"y)))
3332adantr 425 . . . 4 |- ((((J e. Top /\ K e. Top) /\ (A e. (Clsd` J) /\ B e. (Clsd` J) /\ (A u. B) = X) /\ (F:X-->Y /\ (F |` A) e. ((subSp` <.A, J>.) Cn K) /\ (F |` B) e. ((subSp` <.B, J>.) Cn K))) /\ y e. (Clsd` K)) -> (`'F"y) = ((`'(F |` A)"y) u. (`'(F |` B)"y)))
34 simpl1l 927 . . . . 5 |- ((((J e. Top /\ K e. Top) /\ (A e. (Clsd` J) /\ B e. (Clsd` J) /\ (A u. B) = X) /\ (F:X-->Y /\ (F |` A) e. ((subSp` <.A, J>.) Cn K) /\ (F |` B) e. ((subSp` <.B, J>.) Cn K))) /\ y e. (Clsd` K)) -> J e. Top)
35 cnclima 9048 . . . . . . . . . . . . . . . 16 |- ((((subSp` <.A, J>.) e. Top /\ K e. Top /\ (F |` A) e. ((subSp` <.A, J>.) Cn K)) /\ y e. (Clsd` K)) -> (`'(F |` A)"y) e. (Clsd` (subSp` <.A, J>.)))
3635ex 402 . . . . . . . . . . . . . . 15 |- (((subSp` <.A, J>.) e. Top /\ K e. Top /\ (F |` A) e. ((subSp` <.A, J>.) Cn K)) -> (y e. (Clsd` K) -> (`'(F |` A)"y) e. (Clsd` (subSp` <.A, J>.))))
37363expia 1069 . . . . . . . . . . . . . 14 |- (((subSp` <.A, J>.) e. Top /\ K e. Top) -> ((F |` A) e. ((subSp` <.A, J>.) Cn K) -> (y e. (Clsd` K) -> (`'(F |` A)"y) e. (Clsd` (subSp` <.A, J>.)))))
38 eqid 1884 . . . . . . . . . . . . . . . 16 |- U.J = U.J
3938cldss 8947 . . . . . . . . . . . . . . 15 |- ((J e. Top /\ A e. (Clsd` J)) -> A C_ U.J)
40 stoig3 10253 . . . . . . . . . . . . . . 15 |- ((J e. Top /\ A C_ U.J) -> (subSp` <.A, J>.) e. Top)
4139, 40syldan 516 . . . . . . . . . . . . . 14 |- ((J e. Top /\ A e. (Clsd` J)) -> (subSp` <.A, J>.) e. Top)
4237, 41sylan 497 . . . . . . . . . . . . 13 |- (((J e. Top /\ A e. (Clsd` J)) /\ K e. Top) -> ((F |` A) e. ((subSp` <.A, J>.) Cn K) -> (y e. (Clsd` K) -> (`'(F |` A)"y) e. (Clsd` (subSp` <.A, J>.)))))
4342an1rs 547 . . . . . . . . . . . 12 |- (((J e. Top /\ K e. Top) /\ A e. (Clsd` J)) -> ((F |` A) e. ((subSp` <.A, J>.) Cn K) -> (y e. (Clsd` K) -> (`'(F |` A)"y) e. (Clsd` (subSp` <.A, J>.)))))
4443imp 377 . . . . . . . . . . 11 |- ((((J e. Top /\ K e. Top) /\ A e. (Clsd` J)) /\ (F |` A) e. ((subSp` <.A, J>.) Cn K)) -> (y e. (Clsd` K) -> (`'(F |` A)"y) e. (Clsd` (subSp` <.A, J>.))))
45 subspcld2 15839 . . . . . . . . . . . . . 14 |- ((J e. Top /\ A e. (Clsd` J) /\ (`'(F |` A)"y) e. (Clsd` (subSp` <.A, J>.))) -> (`'(F |` A)"y) e. (Clsd` J))
46453expia 1069 . . . . . . . . . . . . 13 |- ((J e. Top /\ A e. (Clsd` J)) -> ((`'(F |` A)"y) e. (Clsd` (subSp` <.A, J>.)) -> (`'(F |` A)"y) e. (Clsd` J)))
4746adantlr 429 . . . . . . . . . . . 12 |- (((J e. Top /\ K e. Top) /\ A e. (Clsd` J)) -> ((`'(F |` A)"y) e. (Clsd` (subSp` <.A, J>.)) -> (`'(F |` A)"y) e. (Clsd` J)))
4847adantr 425 . . . . . . . . . . 11 |- ((((J e. Top /\ K e. Top) /\ A e. (Clsd` J)) /\ (F |` A) e. ((subSp` <.A, J>.) Cn K)) -> ((`'(F |` A)"y) e. (Clsd` (subSp` <.A, J>.)) -> (`'(F |` A)"y) e. (Clsd` J)))
4944, 48syld 30 . . . . . . . . . 10 |- ((((J e. Top /\ K e. Top) /\ A e. (Clsd` J)) /\ (F |` A) e. ((subSp` <.A, J>.) Cn K)) -> (y e. (Clsd` K) -> (`'(F |` A)"y) e. (Clsd` J)))
50493ad2antr2 1042 . . . . . . . . 9 |- ((((J e. Top /\ K e. Top) /\ A e. (Clsd` J)) /\ (F:X-->Y /\ (F |` A) e. ((subSp` <.A, J>.) Cn K) /\ (F |` B) e. ((subSp` <.B, J>.) Cn K))) -> (y e. (Clsd` K) -> (`'(F |` A)"y) e. (Clsd` J)))
5150ex 402 . . . . . . . 8 |- (((J e. Top /\ K e. Top) /\ A e. (Clsd` J)) -> ((F:X-->Y /\ (F |` A) e. ((subSp` <.A, J>.) Cn K) /\ (F |` B) e. ((subSp` <.B, J>.) Cn K)) -> (y e. (Clsd` K) -> (`'(F |` A)"y) e. (Clsd` J))))
52513ad2antr1 1041 . . . . . . 7 |- (((J e. Top /\ K e. Top) /\ (A e. (Clsd` J) /\ B e. (Clsd` J) /\ (A u. B) = X)) -> ((F:X-->Y /\ (F |` A) e. ((subSp` <.A, J>.) Cn K) /\ (F |` B) e. ((subSp` <.B, J>.) Cn K)) -> (y e. (Clsd` K) -> (`'(F |` A)"y) e. (Clsd` J))))
53523impia 1064 . . . . . 6 |- (((J e. Top /\ K e. Top) /\ (A e. (Clsd` J) /\ B e. (Clsd` J) /\ (A u. B) = X) /\ (F:X-->Y /\ (F |` A) e. ((subSp` <.A, J>.) Cn K) /\ (F |` B) e. ((subSp` <.B, J>.) Cn K))) -> (y e. (Clsd` K) -> (`'(F |` A)"y) e. (Clsd` J)))
5453imp 377 . . . . 5 |- ((((J e. Top /\ K e. Top) /\ (A e. (Clsd` J) /\ B e. (Clsd` J) /\ (A u. B) = X) /\ (F:X-->Y /\ (F |` A) e. ((subSp` <.A, J>.) Cn K) /\ (F |` B) e. ((subSp` <.B, J>.) Cn K))) /\ y e. (Clsd` K)) -> (`'(F |` A)"y) e. (Clsd` J))
55 cnclima 9048 . . . . . . . . . . . . . . . 16 |- ((((subSp` <.B, J>.) e. Top /\ K e. Top /\ (F |` B) e. ((subSp` <.B, J>.) Cn K)) /\ y e. (Clsd` K)) -> (`'(F |` B)"y) e. (Clsd` (subSp` <.B, J>.)))
5655ex 402 . . . . . . . . . . . . . . 15 |- (((subSp` <.B, J>.) e. Top /\ K e. Top /\ (F |` B) e. ((subSp` <.B, J>.) Cn K)) -> (y e. (Clsd` K) -> (`'(F |` B)"y) e. (Clsd` (subSp` <.B, J>.))))
57563expia 1069 . . . . . . . . . . . . . 14 |- (((subSp` <.B, J>.) e. Top /\ K e. Top) -> ((F |` B) e. ((subSp` <.B, J>.) Cn K) -> (y e. (Clsd` K) -> (`'(F |` B)"y) e. (Clsd` (subSp` <.B, J>.)))))
5838cldss 8947 . . . . . . . . . . . . . . 15 |- ((J e. Top /\ B e. (Clsd` J)) -> B C_ U.J)
59 stoig3 10253 . . . . . . . . . . . . . . 15 |- ((J e. Top /\ B C_ U.J) -> (subSp` <.B, J>.) e. Top)
6058, 59syldan 516 . . . . . . . . . . . . . 14 |- ((J e. Top /\ B e. (Clsd` J)) -> (subSp` <.B, J>.) e. Top)
6157, 60sylan 497 . . . . . . . . . . . . 13 |- (((J e. Top /\ B e. (Clsd` J)) /\ K e. Top) -> ((F |` B) e. ((subSp` <.B, J>.) Cn K) -> (y e. (Clsd` K) -> (`'(F |` B)"y) e. (Clsd` (subSp` <.B, J>.)))))
6261an1rs 547 . . . . . . . . . . . 12 |- (((J e. Top /\ K e. Top) /\ B e. (Clsd` J)) -> ((F |` B) e. ((subSp` <.B, J>.) Cn K) -> (y e. (Clsd` K) -> (`'(F |` B)"y) e. (Clsd` (subSp` <.B, J>.)))))
6362imp 377 . . . . . . . . . . 11 |- ((((J e. Top /\ K e. Top) /\ B e. (Clsd` J)) /\ (F |` B) e. ((subSp` <.B, J>.) Cn K)) -> (y e. (Clsd` K) -> (`'(F |` B)"y) e. (Clsd` (subSp` <.B, J>.))))
64 subspcld2 15839 . . . . . . . . . . . . . 14 |- ((J e. Top /\ B e. (Clsd` J) /\ (`'(F |` B)"y) e. (Clsd` (subSp` <.B, J>.))) -> (`'(F |` B)"y) e. (Clsd` J))
65643expia 1069 . . . . . . . . . . . . 13 |- ((J e. Top /\ B e. (Clsd` J)) -> ((`'(F |` B)"y) e. (Clsd` (subSp` <.B, J>.)) -> (`'(F |` B)"y) e. (Clsd` J)))
6665adantlr 429 . . . . . . . . . . . 12 |- (((J e. Top /\ K e. Top) /\ B e. (Clsd` J)) -> ((`'(F |` B)"y) e. (Clsd` (subSp` <.B, J>.)) -> (`'(F |` B)"y) e. (Clsd` J)))
6766adantr 425 . . . . . . . . . . 11 |- ((((J e. Top /\ K e. Top) /\ B e. (Clsd` J)) /\ (F |` B) e. ((subSp` <.B, J>.) Cn K)) -> ((`'(F |` B)"y) e. (Clsd` (subSp` <.B, J>.)) -> (`'(F |` B)"y) e. (Clsd` J)))
6863, 67syld 30 . . . . . . . . . 10 |- ((((J e. Top /\ K e. Top) /\ B e. (Clsd` J)) /\ (F |` B) e. ((subSp` <.B, J>.) Cn K)) -> (y e. (Clsd` K) -> (`'(F |` B)"y) e. (Clsd` J)))
69683ad2antr3 1043 . . . . . . . . 9 |- ((((J e. Top /\ K e. Top) /\ B e. (Clsd` J)) /\ (F:X-->Y /\ (F |` A) e. ((subSp` <.A, J>.) Cn K) /\ (F |` B) e. ((subSp` <.B, J>.) Cn K))) -> (y e. (Clsd` K) -> (`'(F |` B)"y) e. (Clsd` J)))
7069ex 402 . . . . . . . 8 |- (((J e. Top /\ K e. Top) /\ B e. (Clsd` J)) -> ((F:X-->Y /\ (F |` A) e. ((subSp` <.A, J>.) Cn K) /\ (F |` B) e. ((subSp` <.B, J>.) Cn K)) -> (y e. (Clsd` K) -> (`'(F |` B)"y) e. (Clsd` J))))
71703ad2antr2 1042 . . . . . . 7 |- (((J e. Top /\ K e. Top) /\ (A e. (Clsd` J) /\ B e. (Clsd` J) /\ (A u. B) = X)) -> ((F:X-->Y /\ (F |` A) e. ((subSp` <.A, J>.) Cn K) /\ (F |` B) e. ((subSp` <.B, J>.) Cn K)) -> (y e. (Clsd` K) -> (`'(F |` B)"y) e. (Clsd` J))))
72713impia 1064 . . . . . 6 |- (((J e. Top /\ K e. Top) /\ (A e. (Clsd` J) /\ B e. (Clsd` J) /\ (A u. B) = X) /\ (F:X-->Y /\ (F |` A) e. ((subSp` <.A, J>.) Cn K) /\ (F |` B) e. ((subSp` <.B, J>.) Cn K))) -> (y e. (Clsd` K) -> (`'(F |` B)"y) e. (Clsd` J)))
7372imp 377 . . . . 5 |- ((((J e. Top /\ K e. Top) /\ (A e. (Clsd` J) /\ B e. (Clsd` J) /\ (A u. B) = X) /\ (F:X-->Y /\ (F |` A) e. ((subSp` <.A, J>.) Cn K) /\ (F |` B) e. ((subSp` <.B, J>.) Cn K))) /\ y e. (Clsd` K)) -> (`'(F |` B)"y) e. (Clsd` J))
74 uncld 8957 . . . . 5 |- ((J e. Top /\ (`'(F |` A)"y) e. (Clsd` J) /\ (`'(F |` B)"y) e. (Clsd` J)) -> ((`'(F |` A)"y) u. (`'(F |` B)"y)) e. (Clsd` J))
7534, 54, 73, 74syl111anc 1100 . . . 4 |- ((((J e. Top /\ K e. Top) /\ (A e. (Clsd` J) /\ B e. (Clsd` J) /\ (A u. B) = X) /\ (F:X-->Y /\ (F |` A) e. ((subSp` <.A, J>.) Cn K) /\ (F |` B) e. ((subSp` <.B, J>.) Cn K))) /\ y e. (Clsd` K)) -> ((`'(F |` A)"y) u. (`'(F |` B)"y)) e. (Clsd` J))
7633, 75eqeltrd 1971 . . 3 |- ((((J e. Top /\ K e. Top) /\ (A e. (Clsd` J) /\ B e. (Clsd` J) /\ (A u. B) = X) /\ (F:X-->Y /\ (F |` A) e. ((subSp` <.A, J>.) Cn K) /\ (F |` B) e. ((subSp` <.B, J>.) Cn K))) /\ y e. (Clsd` K)) -> (`'F"y) e. (Clsd` J))
7776r19.21aiva 2176 . 2 |- (((J e. Top /\ K e. Top) /\ (A e. (Clsd` J) /\ B e. (Clsd` J) /\ (A u. B) = X) /\ (F:X-->Y /\ (F |` A) e. ((subSp` <.A, J>.) Cn K) /\ (F |` B) e. ((subSp` <.B, J>.) Cn K))) -> A.y e. (Clsd` K)(`'F"y) e. (Clsd` J))
784, 6, 77mpbir2and 802 1 |- (((J e. Top /\ K e. Top) /\ (A e. (Clsd` J) /\ B e. (Clsd` J) /\ (A u. B) = X) /\ (F:X-->Y /\ (F |` A) e. ((subSp` <.A, J>.) Cn K) /\ (F |` B) e. ((subSp` <.B, J>.) Cn K))) -> F e. (J Cn K))
Colors of variables: wff set class
Syntax hints:   -> wi 3   <-> wb 163   /\ wa 240   /\ w3a 858   = wceq 1298   e. wcel 1300  A.wral 2105   u. cun 2591   i^i cin 2592   C_ wss 2593  <.cop 3046  U.cuni 3177  `'ccnv 3985  dom cdm 3986  ran crn 3987   |` cres 3988  "cima 3989  Fun wfun 3992  -->wf 3994  ` cfv 3998  (class class class)co 4884  Topctop 8857  Clsdccld 8936   Cn ccn 9028  subSpcsubsp 10242
This theorem is referenced by:  piececn 15894  phtpycolem5 16055  pcocn 16076  pcohtpylem3 16082  pcorevlem 16086
This theorem was proved from axioms:  ax-1 4  ax-2 5  ax-3 6  ax-mp 7  ax-7 1304  ax-gen 1305  ax-8 1306  ax-9 1307  ax-10 1308  ax-11 1309  ax-12 1310  ax-13 1311  ax-14 1312  ax-17 1317  ax-4 1319  ax-5o 1321  ax-6o 1324  ax-9o 1481  ax-10o 1500  ax-16 1580  ax-11o 1588  ax-ext 1865  ax-rep 3428  ax-sep 3438  ax-nul 3445  ax-pow 3481  ax-pr 3524  ax-un 3790  ax-reg 5695
This theorem depends on definitions:  df-bi 164  df-or 241  df-an 242  df-3an 860  df-ex 1327  df-sb 1536  df-eu 1775  df-mo 1776  df-clab 1872  df-cleq 1877  df-clel 1880  df-ne 2019  df-ral 2109  df-rex 2110  df-rab 2112  df-v 2294  df-sbc 2454  df-csb 2541  df-dif 2597  df-un 2600  df-in 2603  df-ss 2605  df-nul 2876  df-if 2983  df-pw 3035  df-sn 3049  df-pr 3050  df-op 3053  df-uni 3178  df-int 3215  df-iun 3257  df-iin 3258  df-br 3339  df-opab 3396  df-id 3586  df-xp 4000  df-rel 4001  df-cnv 4002  df-co 4003  df-dm 4004  df-rn 4005  df-res 4006  df-ima 4007  df-fun 4008  df-fn 4009  df-f 4010  df-fv 4014  df-opr 4886  df-oprab 4887  df-map 5383  df-top 8861  df-topsp 8862  df-cld 8939  df-cn 9030  df-subsp 10243
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