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Theorem mapunen 7141
Description: Equinumerosity law for set exponentiation of a disjoint union. Exercise 4.45 of [Mendelson] p. 255. (Contributed by NM, 23-Sep-2004.) (Revised by Mario Carneiro, 29-Apr-2015.)
Assertion
Ref Expression
mapunen (((𝐴𝑉𝐵𝑊𝐶𝑋) ∧ (𝐴𝐵) = ∅) → (𝐶𝑚 (𝐴𝐵)) ≈ ((𝐶𝑚 𝐴) × (𝐶𝑚 𝐵)))

Proof of Theorem mapunen
Dummy variables 𝑥 𝑦 are mutually distinct and distinct from all other variables.
StepHypRef Expression
1 fnmap 6919 . . 3 𝑚 Fn (V × V)
2 simpl3 1033 . . . 4 (((𝐴𝑉𝐵𝑊𝐶𝑋) ∧ (𝐴𝐵) = ∅) → 𝐶𝑋)
32elexd 2835 . . 3 (((𝐴𝑉𝐵𝑊𝐶𝑋) ∧ (𝐴𝐵) = ∅) → 𝐶 ∈ V)
4 simpl1 1031 . . . 4 (((𝐴𝑉𝐵𝑊𝐶𝑋) ∧ (𝐴𝐵) = ∅) → 𝐴𝑉)
5 simpl2 1032 . . . 4 (((𝐴𝑉𝐵𝑊𝐶𝑋) ∧ (𝐴𝐵) = ∅) → 𝐵𝑊)
64, 5unexd 4887 . . 3 (((𝐴𝑉𝐵𝑊𝐶𝑋) ∧ (𝐴𝐵) = ∅) → (𝐴𝐵) ∈ V)
7 fnovex 6108 . . 3 (( ↑𝑚 Fn (V × V) ∧ 𝐶 ∈ V ∧ (𝐴𝐵) ∈ V) → (𝐶𝑚 (𝐴𝐵)) ∈ V)
81, 3, 6, 7mp3an2i 1383 . 2 (((𝐴𝑉𝐵𝑊𝐶𝑋) ∧ (𝐴𝐵) = ∅) → (𝐶𝑚 (𝐴𝐵)) ∈ V)
94elexd 2835 . . . 4 (((𝐴𝑉𝐵𝑊𝐶𝑋) ∧ (𝐴𝐵) = ∅) → 𝐴 ∈ V)
10 fnovex 6108 . . . 4 (( ↑𝑚 Fn (V × V) ∧ 𝐶 ∈ V ∧ 𝐴 ∈ V) → (𝐶𝑚 𝐴) ∈ V)
111, 3, 9, 10mp3an2i 1383 . . 3 (((𝐴𝑉𝐵𝑊𝐶𝑋) ∧ (𝐴𝐵) = ∅) → (𝐶𝑚 𝐴) ∈ V)
125elexd 2835 . . . 4 (((𝐴𝑉𝐵𝑊𝐶𝑋) ∧ (𝐴𝐵) = ∅) → 𝐵 ∈ V)
13 fnovex 6108 . . . 4 (( ↑𝑚 Fn (V × V) ∧ 𝐶 ∈ V ∧ 𝐵 ∈ V) → (𝐶𝑚 𝐵) ∈ V)
141, 3, 12, 13mp3an2i 1383 . . 3 (((𝐴𝑉𝐵𝑊𝐶𝑋) ∧ (𝐴𝐵) = ∅) → (𝐶𝑚 𝐵) ∈ V)
1511, 14xpexd 4885 . 2 (((𝐴𝑉𝐵𝑊𝐶𝑋) ∧ (𝐴𝐵) = ∅) → ((𝐶𝑚 𝐴) × (𝐶𝑚 𝐵)) ∈ V)
16 elmapi 6934 . . . . 5 (𝑥 ∈ (𝐶𝑚 (𝐴𝐵)) → 𝑥:(𝐴𝐵)⟶𝐶)
17 ssun1 3392 . . . . 5 𝐴 ⊆ (𝐴𝐵)
18 fssres 5560 . . . . 5 ((𝑥:(𝐴𝐵)⟶𝐶𝐴 ⊆ (𝐴𝐵)) → (𝑥𝐴):𝐴𝐶)
1916, 17, 18sylancl 417 . . . 4 (𝑥 ∈ (𝐶𝑚 (𝐴𝐵)) → (𝑥𝐴):𝐴𝐶)
20 ssun2 3393 . . . . 5 𝐵 ⊆ (𝐴𝐵)
21 fssres 5560 . . . . 5 ((𝑥:(𝐴𝐵)⟶𝐶𝐵 ⊆ (𝐴𝐵)) → (𝑥𝐵):𝐵𝐶)
2216, 20, 21sylancl 417 . . . 4 (𝑥 ∈ (𝐶𝑚 (𝐴𝐵)) → (𝑥𝐵):𝐵𝐶)
2319, 22jca 306 . . 3 (𝑥 ∈ (𝐶𝑚 (𝐴𝐵)) → ((𝑥𝐴):𝐴𝐶 ∧ (𝑥𝐵):𝐵𝐶))
24 opelxp 4799 . . . 4 (⟨(𝑥𝐴), (𝑥𝐵)⟩ ∈ ((𝐶𝑚 𝐴) × (𝐶𝑚 𝐵)) ↔ ((𝑥𝐴) ∈ (𝐶𝑚 𝐴) ∧ (𝑥𝐵) ∈ (𝐶𝑚 𝐵)))
252, 4elmapd 6926 . . . . 5 (((𝐴𝑉𝐵𝑊𝐶𝑋) ∧ (𝐴𝐵) = ∅) → ((𝑥𝐴) ∈ (𝐶𝑚 𝐴) ↔ (𝑥𝐴):𝐴𝐶))
262, 5elmapd 6926 . . . . 5 (((𝐴𝑉𝐵𝑊𝐶𝑋) ∧ (𝐴𝐵) = ∅) → ((𝑥𝐵) ∈ (𝐶𝑚 𝐵) ↔ (𝑥𝐵):𝐵𝐶))
2725, 26anbi12d 477 . . . 4 (((𝐴𝑉𝐵𝑊𝐶𝑋) ∧ (𝐴𝐵) = ∅) → (((𝑥𝐴) ∈ (𝐶𝑚 𝐴) ∧ (𝑥𝐵) ∈ (𝐶𝑚 𝐵)) ↔ ((𝑥𝐴):𝐴𝐶 ∧ (𝑥𝐵):𝐵𝐶)))
2824, 27bitrid 192 . . 3 (((𝐴𝑉𝐵𝑊𝐶𝑋) ∧ (𝐴𝐵) = ∅) → (⟨(𝑥𝐴), (𝑥𝐵)⟩ ∈ ((𝐶𝑚 𝐴) × (𝐶𝑚 𝐵)) ↔ ((𝑥𝐴):𝐴𝐶 ∧ (𝑥𝐵):𝐵𝐶)))
2923, 28imbitrrid 156 . 2 (((𝐴𝑉𝐵𝑊𝐶𝑋) ∧ (𝐴𝐵) = ∅) → (𝑥 ∈ (𝐶𝑚 (𝐴𝐵)) → ⟨(𝑥𝐴), (𝑥𝐵)⟩ ∈ ((𝐶𝑚 𝐴) × (𝐶𝑚 𝐵))))
30 xp1st 6389 . . . . . . 7 (𝑦 ∈ ((𝐶𝑚 𝐴) × (𝐶𝑚 𝐵)) → (1st𝑦) ∈ (𝐶𝑚 𝐴))
3130adantl 277 . . . . . 6 ((((𝐴𝑉𝐵𝑊𝐶𝑋) ∧ (𝐴𝐵) = ∅) ∧ 𝑦 ∈ ((𝐶𝑚 𝐴) × (𝐶𝑚 𝐵))) → (1st𝑦) ∈ (𝐶𝑚 𝐴))
32 elmapi 6934 . . . . . 6 ((1st𝑦) ∈ (𝐶𝑚 𝐴) → (1st𝑦):𝐴𝐶)
3331, 32syl 14 . . . . 5 ((((𝐴𝑉𝐵𝑊𝐶𝑋) ∧ (𝐴𝐵) = ∅) ∧ 𝑦 ∈ ((𝐶𝑚 𝐴) × (𝐶𝑚 𝐵))) → (1st𝑦):𝐴𝐶)
34 xp2nd 6390 . . . . . . 7 (𝑦 ∈ ((𝐶𝑚 𝐴) × (𝐶𝑚 𝐵)) → (2nd𝑦) ∈ (𝐶𝑚 𝐵))
3534adantl 277 . . . . . 6 ((((𝐴𝑉𝐵𝑊𝐶𝑋) ∧ (𝐴𝐵) = ∅) ∧ 𝑦 ∈ ((𝐶𝑚 𝐴) × (𝐶𝑚 𝐵))) → (2nd𝑦) ∈ (𝐶𝑚 𝐵))
36 elmapi 6934 . . . . . 6 ((2nd𝑦) ∈ (𝐶𝑚 𝐵) → (2nd𝑦):𝐵𝐶)
3735, 36syl 14 . . . . 5 ((((𝐴𝑉𝐵𝑊𝐶𝑋) ∧ (𝐴𝐵) = ∅) ∧ 𝑦 ∈ ((𝐶𝑚 𝐴) × (𝐶𝑚 𝐵))) → (2nd𝑦):𝐵𝐶)
38 simplr 533 . . . . 5 ((((𝐴𝑉𝐵𝑊𝐶𝑋) ∧ (𝐴𝐵) = ∅) ∧ 𝑦 ∈ ((𝐶𝑚 𝐴) × (𝐶𝑚 𝐵))) → (𝐴𝐵) = ∅)
3933, 37, 38fun2d 5558 . . . 4 ((((𝐴𝑉𝐵𝑊𝐶𝑋) ∧ (𝐴𝐵) = ∅) ∧ 𝑦 ∈ ((𝐶𝑚 𝐴) × (𝐶𝑚 𝐵))) → ((1st𝑦) ∪ (2nd𝑦)):(𝐴𝐵)⟶𝐶)
4039ex 115 . . 3 (((𝐴𝑉𝐵𝑊𝐶𝑋) ∧ (𝐴𝐵) = ∅) → (𝑦 ∈ ((𝐶𝑚 𝐴) × (𝐶𝑚 𝐵)) → ((1st𝑦) ∪ (2nd𝑦)):(𝐴𝐵)⟶𝐶))
412, 6elmapd 6926 . . 3 (((𝐴𝑉𝐵𝑊𝐶𝑋) ∧ (𝐴𝐵) = ∅) → (((1st𝑦) ∪ (2nd𝑦)) ∈ (𝐶𝑚 (𝐴𝐵)) ↔ ((1st𝑦) ∪ (2nd𝑦)):(𝐴𝐵)⟶𝐶))
4240, 41sylibrd 169 . 2 (((𝐴𝑉𝐵𝑊𝐶𝑋) ∧ (𝐴𝐵) = ∅) → (𝑦 ∈ ((𝐶𝑚 𝐴) × (𝐶𝑚 𝐵)) → ((1st𝑦) ∪ (2nd𝑦)) ∈ (𝐶𝑚 (𝐴𝐵))))
43 1st2nd2 6399 . . . . . . 7 (𝑦 ∈ ((𝐶𝑚 𝐴) × (𝐶𝑚 𝐵)) → 𝑦 = ⟨(1st𝑦), (2nd𝑦)⟩)
4443ad2antll 495 . . . . . 6 ((((𝐴𝑉𝐵𝑊𝐶𝑋) ∧ (𝐴𝐵) = ∅) ∧ (𝑥 ∈ (𝐶𝑚 (𝐴𝐵)) ∧ 𝑦 ∈ ((𝐶𝑚 𝐴) × (𝐶𝑚 𝐵)))) → 𝑦 = ⟨(1st𝑦), (2nd𝑦)⟩)
4533adantrl 482 . . . . . . . 8 ((((𝐴𝑉𝐵𝑊𝐶𝑋) ∧ (𝐴𝐵) = ∅) ∧ (𝑥 ∈ (𝐶𝑚 (𝐴𝐵)) ∧ 𝑦 ∈ ((𝐶𝑚 𝐴) × (𝐶𝑚 𝐵)))) → (1st𝑦):𝐴𝐶)
4637adantrl 482 . . . . . . . 8 ((((𝐴𝑉𝐵𝑊𝐶𝑋) ∧ (𝐴𝐵) = ∅) ∧ (𝑥 ∈ (𝐶𝑚 (𝐴𝐵)) ∧ 𝑦 ∈ ((𝐶𝑚 𝐴) × (𝐶𝑚 𝐵)))) → (2nd𝑦):𝐵𝐶)
47 simplr 533 . . . . . . . 8 ((((𝐴𝑉𝐵𝑊𝐶𝑋) ∧ (𝐴𝐵) = ∅) ∧ (𝑥 ∈ (𝐶𝑚 (𝐴𝐵)) ∧ 𝑦 ∈ ((𝐶𝑚 𝐴) × (𝐶𝑚 𝐵)))) → (𝐴𝐵) = ∅)
48 fresaunres1disj 5566 . . . . . . . 8 (((1st𝑦):𝐴𝐶 ∧ (2nd𝑦):𝐵𝐶 ∧ (𝐴𝐵) = ∅) → (((1st𝑦) ∪ (2nd𝑦)) ↾ 𝐴) = (1st𝑦))
4945, 46, 47, 48syl3anc 1278 . . . . . . 7 ((((𝐴𝑉𝐵𝑊𝐶𝑋) ∧ (𝐴𝐵) = ∅) ∧ (𝑥 ∈ (𝐶𝑚 (𝐴𝐵)) ∧ 𝑦 ∈ ((𝐶𝑚 𝐴) × (𝐶𝑚 𝐵)))) → (((1st𝑦) ∪ (2nd𝑦)) ↾ 𝐴) = (1st𝑦))
50 fresaunres2disj 5565 . . . . . . . 8 (((1st𝑦):𝐴𝐶 ∧ (2nd𝑦):𝐵𝐶 ∧ (𝐴𝐵) = ∅) → (((1st𝑦) ∪ (2nd𝑦)) ↾ 𝐵) = (2nd𝑦))
5145, 46, 47, 50syl3anc 1278 . . . . . . 7 ((((𝐴𝑉𝐵𝑊𝐶𝑋) ∧ (𝐴𝐵) = ∅) ∧ (𝑥 ∈ (𝐶𝑚 (𝐴𝐵)) ∧ 𝑦 ∈ ((𝐶𝑚 𝐴) × (𝐶𝑚 𝐵)))) → (((1st𝑦) ∪ (2nd𝑦)) ↾ 𝐵) = (2nd𝑦))
5249, 51opeq12d 3907 . . . . . 6 ((((𝐴𝑉𝐵𝑊𝐶𝑋) ∧ (𝐴𝐵) = ∅) ∧ (𝑥 ∈ (𝐶𝑚 (𝐴𝐵)) ∧ 𝑦 ∈ ((𝐶𝑚 𝐴) × (𝐶𝑚 𝐵)))) → ⟨(((1st𝑦) ∪ (2nd𝑦)) ↾ 𝐴), (((1st𝑦) ∪ (2nd𝑦)) ↾ 𝐵)⟩ = ⟨(1st𝑦), (2nd𝑦)⟩)
5344, 52eqtr4d 2274 . . . . 5 ((((𝐴𝑉𝐵𝑊𝐶𝑋) ∧ (𝐴𝐵) = ∅) ∧ (𝑥 ∈ (𝐶𝑚 (𝐴𝐵)) ∧ 𝑦 ∈ ((𝐶𝑚 𝐴) × (𝐶𝑚 𝐵)))) → 𝑦 = ⟨(((1st𝑦) ∪ (2nd𝑦)) ↾ 𝐴), (((1st𝑦) ∪ (2nd𝑦)) ↾ 𝐵)⟩)
54 reseq1 5052 . . . . . . 7 (𝑥 = ((1st𝑦) ∪ (2nd𝑦)) → (𝑥𝐴) = (((1st𝑦) ∪ (2nd𝑦)) ↾ 𝐴))
55 reseq1 5052 . . . . . . 7 (𝑥 = ((1st𝑦) ∪ (2nd𝑦)) → (𝑥𝐵) = (((1st𝑦) ∪ (2nd𝑦)) ↾ 𝐵))
5654, 55opeq12d 3907 . . . . . 6 (𝑥 = ((1st𝑦) ∪ (2nd𝑦)) → ⟨(𝑥𝐴), (𝑥𝐵)⟩ = ⟨(((1st𝑦) ∪ (2nd𝑦)) ↾ 𝐴), (((1st𝑦) ∪ (2nd𝑦)) ↾ 𝐵)⟩)
5756eqeq2d 2250 . . . . 5 (𝑥 = ((1st𝑦) ∪ (2nd𝑦)) → (𝑦 = ⟨(𝑥𝐴), (𝑥𝐵)⟩ ↔ 𝑦 = ⟨(((1st𝑦) ∪ (2nd𝑦)) ↾ 𝐴), (((1st𝑦) ∪ (2nd𝑦)) ↾ 𝐵)⟩))
5853, 57syl5ibrcom 157 . . . 4 ((((𝐴𝑉𝐵𝑊𝐶𝑋) ∧ (𝐴𝐵) = ∅) ∧ (𝑥 ∈ (𝐶𝑚 (𝐴𝐵)) ∧ 𝑦 ∈ ((𝐶𝑚 𝐴) × (𝐶𝑚 𝐵)))) → (𝑥 = ((1st𝑦) ∪ (2nd𝑦)) → 𝑦 = ⟨(𝑥𝐴), (𝑥𝐵)⟩))
59 ffn 5528 . . . . . . . 8 (𝑥:(𝐴𝐵)⟶𝐶𝑥 Fn (𝐴𝐵))
60 fnresdm 5487 . . . . . . . 8 (𝑥 Fn (𝐴𝐵) → (𝑥 ↾ (𝐴𝐵)) = 𝑥)
6116, 59, 603syl 17 . . . . . . 7 (𝑥 ∈ (𝐶𝑚 (𝐴𝐵)) → (𝑥 ↾ (𝐴𝐵)) = 𝑥)
6261ad2antrl 494 . . . . . 6 ((((𝐴𝑉𝐵𝑊𝐶𝑋) ∧ (𝐴𝐵) = ∅) ∧ (𝑥 ∈ (𝐶𝑚 (𝐴𝐵)) ∧ 𝑦 ∈ ((𝐶𝑚 𝐴) × (𝐶𝑚 𝐵)))) → (𝑥 ↾ (𝐴𝐵)) = 𝑥)
6362eqcomd 2244 . . . . 5 ((((𝐴𝑉𝐵𝑊𝐶𝑋) ∧ (𝐴𝐵) = ∅) ∧ (𝑥 ∈ (𝐶𝑚 (𝐴𝐵)) ∧ 𝑦 ∈ ((𝐶𝑚 𝐴) × (𝐶𝑚 𝐵)))) → 𝑥 = (𝑥 ↾ (𝐴𝐵)))
64 vex 2824 . . . . . . . . . 10 𝑥 ∈ V
6564resex 5099 . . . . . . . . 9 (𝑥𝐴) ∈ V
6664resex 5099 . . . . . . . . 9 (𝑥𝐵) ∈ V
6765, 66op1std 6372 . . . . . . . 8 (𝑦 = ⟨(𝑥𝐴), (𝑥𝐵)⟩ → (1st𝑦) = (𝑥𝐴))
6865, 66op2ndd 6373 . . . . . . . 8 (𝑦 = ⟨(𝑥𝐴), (𝑥𝐵)⟩ → (2nd𝑦) = (𝑥𝐵))
6967, 68uneq12d 3384 . . . . . . 7 (𝑦 = ⟨(𝑥𝐴), (𝑥𝐵)⟩ → ((1st𝑦) ∪ (2nd𝑦)) = ((𝑥𝐴) ∪ (𝑥𝐵)))
70 resundi 5071 . . . . . . 7 (𝑥 ↾ (𝐴𝐵)) = ((𝑥𝐴) ∪ (𝑥𝐵))
7169, 70eqtr4di 2289 . . . . . 6 (𝑦 = ⟨(𝑥𝐴), (𝑥𝐵)⟩ → ((1st𝑦) ∪ (2nd𝑦)) = (𝑥 ↾ (𝐴𝐵)))
7271eqeq2d 2250 . . . . 5 (𝑦 = ⟨(𝑥𝐴), (𝑥𝐵)⟩ → (𝑥 = ((1st𝑦) ∪ (2nd𝑦)) ↔ 𝑥 = (𝑥 ↾ (𝐴𝐵))))
7363, 72syl5ibrcom 157 . . . 4 ((((𝐴𝑉𝐵𝑊𝐶𝑋) ∧ (𝐴𝐵) = ∅) ∧ (𝑥 ∈ (𝐶𝑚 (𝐴𝐵)) ∧ 𝑦 ∈ ((𝐶𝑚 𝐴) × (𝐶𝑚 𝐵)))) → (𝑦 = ⟨(𝑥𝐴), (𝑥𝐵)⟩ → 𝑥 = ((1st𝑦) ∪ (2nd𝑦))))
7458, 73impbid 129 . . 3 ((((𝐴𝑉𝐵𝑊𝐶𝑋) ∧ (𝐴𝐵) = ∅) ∧ (𝑥 ∈ (𝐶𝑚 (𝐴𝐵)) ∧ 𝑦 ∈ ((𝐶𝑚 𝐴) × (𝐶𝑚 𝐵)))) → (𝑥 = ((1st𝑦) ∪ (2nd𝑦)) ↔ 𝑦 = ⟨(𝑥𝐴), (𝑥𝐵)⟩))
7574ex 115 . 2 (((𝐴𝑉𝐵𝑊𝐶𝑋) ∧ (𝐴𝐵) = ∅) → ((𝑥 ∈ (𝐶𝑚 (𝐴𝐵)) ∧ 𝑦 ∈ ((𝐶𝑚 𝐴) × (𝐶𝑚 𝐵))) → (𝑥 = ((1st𝑦) ∪ (2nd𝑦)) ↔ 𝑦 = ⟨(𝑥𝐴), (𝑥𝐵)⟩)))
768, 15, 29, 42, 75en3d 7045 1 (((𝐴𝑉𝐵𝑊𝐶𝑋) ∧ (𝐴𝐵) = ∅) → (𝐶𝑚 (𝐴𝐵)) ≈ ((𝐶𝑚 𝐴) × (𝐶𝑚 𝐵)))
Colors of variables: wff set class
Syntax hints:  wi 4  wa 104  wb 105  w3a 1009   = wceq 1402  wcel 2209  Vcvv 2821  cun 3218  cin 3219  wss 3220  c0 3520  cop 3708   class class class wbr 4125   × cxp 4767  cres 4771   Fn wfn 5367  wf 5368  cfv 5372  (class class class)co 6075  1st c1st 6362  2nd c2nd 6363  𝑚 cmap 6912  cen 7010
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 106  ax-ia2 107  ax-ia3 108  ax-in1 623  ax-in2 624  ax-io 721  ax-5 1500  ax-7 1501  ax-gen 1502  ax-ie1 1546  ax-ie2 1547  ax-8 1557  ax-10 1558  ax-11 1559  ax-i12 1560  ax-bndl 1562  ax-4 1563  ax-17 1579  ax-i9 1583  ax-ial 1587  ax-i5r 1588  ax-14 2212  ax-ext 2220  ax-sep 4244  ax-pow 4306  ax-pr 4341  ax-un 4573  ax-setind 4679
This theorem depends on definitions:  df-bi 117  df-3an 1011  df-tru 1405  df-fal 1408  df-nf 1514  df-sb 1816  df-eu 2089  df-mo 2090  df-clab 2225  df-cleq 2231  df-clel 2234  df-nfc 2381  df-ne 2421  df-ral 2533  df-rex 2534  df-rab 2537  df-v 2823  df-sbc 3052  df-csb 3148  df-dif 3222  df-un 3224  df-in 3226  df-ss 3233  df-nul 3521  df-pw 3687  df-sn 3711  df-pr 3712  df-op 3714  df-uni 3931  df-iun 4009  df-br 4126  df-opab 4188  df-mpt 4189  df-id 4433  df-xp 4775  df-rel 4776  df-cnv 4777  df-co 4778  df-dm 4779  df-rn 4780  df-res 4781  df-ima 4782  df-iota 5332  df-fun 5374  df-fn 5375  df-f 5376  df-f1 5377  df-fo 5378  df-f1o 5379  df-fv 5380  df-ov 6078  df-oprab 6079  df-mpo 6080  df-1st 6364  df-2nd 6365  df-map 6914  df-en 7013
This theorem is referenced by:  mapfi  7251  hashmap  11246
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