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Theorem restnlly 23781
Description: If the property 𝐴 passes to open subspaces, then a space is n-locally 𝐴 iff it is locally 𝐴. (Contributed by Mario Carneiro, 2-Mar-2015.)
Hypothesis
Ref Expression
restlly.1 ((𝜑 ∧ (𝑗 ∈ 𝐴 ∧ 𝑥 ∈ 𝑗)) → (𝑗 ↾t 𝑥) ∈ 𝐴)
Assertion
Ref Expression
restnlly (𝜑 → 𝑛-Locally 𝐴 = Locally 𝐴)
Distinct variable groups:   𝑥,𝑗,𝐴   𝜑,𝑗,𝑥

Proof of Theorem restnlly
Dummy variables 𝑘 𝑠 𝑢 𝑦 are mutually distinct and distinct from all other variables.
StepHypRef Expression
1 nllytop 23772 . . . . . 6 (𝑘 ∈ 𝑛-Locally 𝐴 → 𝑘 ∈ Top)
21adantl 487 . . . . 5 ((𝜑 ∧ 𝑘 ∈ 𝑛-Locally 𝐴) → 𝑘 ∈ Top)
3 nlly2i 23775 . . . . . . . . 9 ((𝑘 ∈ 𝑛-Locally 𝐴 ∧ 𝑦 ∈ 𝑘 ∧ 𝑢 ∈ 𝑦) → ∃𝑠 ∈ 𝒫 𝑦∃𝑥 ∈ 𝑘 (𝑢 ∈ 𝑥 ∧ 𝑥 ⊆ 𝑠 ∧ (𝑘 ↾t 𝑠) ∈ 𝐴))
433adant1l 1195 . . . . . . . 8 (((𝜑 ∧ 𝑘 ∈ 𝑛-Locally 𝐴) ∧ 𝑦 ∈ 𝑘 ∧ 𝑢 ∈ 𝑦) → ∃𝑠 ∈ 𝒫 𝑦∃𝑥 ∈ 𝑘 (𝑢 ∈ 𝑥 ∧ 𝑥 ⊆ 𝑠 ∧ (𝑘 ↾t 𝑠) ∈ 𝐴))
5 simprl 783 . . . . . . . . . . . . 13 (((((𝜑 ∧ 𝑘 ∈ 𝑛-Locally 𝐴) ∧ 𝑦 ∈ 𝑘 ∧ 𝑢 ∈ 𝑦) ∧ 𝑠 ∈ 𝒫 𝑦) ∧ (𝑥 ∈ 𝑘 ∧ (𝑢 ∈ 𝑥 ∧ 𝑥 ⊆ 𝑠 ∧ (𝑘 ↾t 𝑠) ∈ 𝐴))) → 𝑥 ∈ 𝑘)
6 simprr2 1241 . . . . . . . . . . . . . . 15 (((((𝜑 ∧ 𝑘 ∈ 𝑛-Locally 𝐴) ∧ 𝑦 ∈ 𝑘 ∧ 𝑢 ∈ 𝑦) ∧ 𝑠 ∈ 𝒫 𝑦) ∧ (𝑥 ∈ 𝑘 ∧ (𝑢 ∈ 𝑥 ∧ 𝑥 ⊆ 𝑠 ∧ (𝑘 ↾t 𝑠) ∈ 𝐴))) → 𝑥 ⊆ 𝑠)
7 simplr 781 . . . . . . . . . . . . . . . 16 (((((𝜑 ∧ 𝑘 ∈ 𝑛-Locally 𝐴) ∧ 𝑦 ∈ 𝑘 ∧ 𝑢 ∈ 𝑦) ∧ 𝑠 ∈ 𝒫 𝑦) ∧ (𝑥 ∈ 𝑘 ∧ (𝑢 ∈ 𝑥 ∧ 𝑥 ⊆ 𝑠 ∧ (𝑘 ↾t 𝑠) ∈ 𝐴))) → 𝑠 ∈ 𝒫 𝑦)
87elpwid 4566 . . . . . . . . . . . . . . 15 (((((𝜑 ∧ 𝑘 ∈ 𝑛-Locally 𝐴) ∧ 𝑦 ∈ 𝑘 ∧ 𝑢 ∈ 𝑦) ∧ 𝑠 ∈ 𝒫 𝑦) ∧ (𝑥 ∈ 𝑘 ∧ (𝑢 ∈ 𝑥 ∧ 𝑥 ⊆ 𝑠 ∧ (𝑘 ↾t 𝑠) ∈ 𝐴))) → 𝑠 ⊆ 𝑦)
96, 8sstrd 3941 . . . . . . . . . . . . . 14 (((((𝜑 ∧ 𝑘 ∈ 𝑛-Locally 𝐴) ∧ 𝑦 ∈ 𝑘 ∧ 𝑢 ∈ 𝑦) ∧ 𝑠 ∈ 𝒫 𝑦) ∧ (𝑥 ∈ 𝑘 ∧ (𝑢 ∈ 𝑥 ∧ 𝑥 ⊆ 𝑠 ∧ (𝑘 ↾t 𝑠) ∈ 𝐴))) → 𝑥 ⊆ 𝑦)
10 velpw 4562 . . . . . . . . . . . . . 14 (𝑥 ∈ 𝒫 𝑦 ↔ 𝑥 ⊆ 𝑦)
119, 10sylibr 237 . . . . . . . . . . . . 13 (((((𝜑 ∧ 𝑘 ∈ 𝑛-Locally 𝐴) ∧ 𝑦 ∈ 𝑘 ∧ 𝑢 ∈ 𝑦) ∧ 𝑠 ∈ 𝒫 𝑦) ∧ (𝑥 ∈ 𝑘 ∧ (𝑢 ∈ 𝑥 ∧ 𝑥 ⊆ 𝑠 ∧ (𝑘 ↾t 𝑠) ∈ 𝐴))) → 𝑥 ∈ 𝒫 𝑦)
125, 11elind 4146 . . . . . . . . . . . 12 (((((𝜑 ∧ 𝑘 ∈ 𝑛-Locally 𝐴) ∧ 𝑦 ∈ 𝑘 ∧ 𝑢 ∈ 𝑦) ∧ 𝑠 ∈ 𝒫 𝑦) ∧ (𝑥 ∈ 𝑘 ∧ (𝑢 ∈ 𝑥 ∧ 𝑥 ⊆ 𝑠 ∧ (𝑘 ↾t 𝑠) ∈ 𝐴))) → 𝑥 ∈ (𝑘 ∩ 𝒫 𝑦))
13 simprr1 1240 . . . . . . . . . . . 12 (((((𝜑 ∧ 𝑘 ∈ 𝑛-Locally 𝐴) ∧ 𝑦 ∈ 𝑘 ∧ 𝑢 ∈ 𝑦) ∧ 𝑠 ∈ 𝒫 𝑦) ∧ (𝑥 ∈ 𝑘 ∧ (𝑢 ∈ 𝑥 ∧ 𝑥 ⊆ 𝑠 ∧ (𝑘 ↾t 𝑠) ∈ 𝐴))) → 𝑢 ∈ 𝑥)
14 simpll1 1231 . . . . . . . . . . . . . . 15 (((((𝜑 ∧ 𝑘 ∈ 𝑛-Locally 𝐴) ∧ 𝑦 ∈ 𝑘 ∧ 𝑢 ∈ 𝑦) ∧ 𝑠 ∈ 𝒫 𝑦) ∧ (𝑥 ∈ 𝑘 ∧ (𝑢 ∈ 𝑥 ∧ 𝑥 ⊆ 𝑠 ∧ (𝑘 ↾t 𝑠) ∈ 𝐴))) → (𝜑 ∧ 𝑘 ∈ 𝑛-Locally 𝐴))
1514, 1simpl2im 513 . . . . . . . . . . . . . 14 (((((𝜑 ∧ 𝑘 ∈ 𝑛-Locally 𝐴) ∧ 𝑦 ∈ 𝑘 ∧ 𝑢 ∈ 𝑦) ∧ 𝑠 ∈ 𝒫 𝑦) ∧ (𝑥 ∈ 𝑘 ∧ (𝑢 ∈ 𝑥 ∧ 𝑥 ⊆ 𝑠 ∧ (𝑘 ↾t 𝑠) ∈ 𝐴))) → 𝑘 ∈ Top)
16 restabs 23463 . . . . . . . . . . . . . 14 ((𝑘 ∈ Top ∧ 𝑥 ⊆ 𝑠 ∧ 𝑠 ∈ 𝒫 𝑦) → ((𝑘 ↾t 𝑠) ↾t 𝑥) = (𝑘 ↾t 𝑥))
1715, 6, 7, 16syl3anc 1398 . . . . . . . . . . . . 13 (((((𝜑 ∧ 𝑘 ∈ 𝑛-Locally 𝐴) ∧ 𝑦 ∈ 𝑘 ∧ 𝑢 ∈ 𝑦) ∧ 𝑠 ∈ 𝒫 𝑦) ∧ (𝑥 ∈ 𝑘 ∧ (𝑢 ∈ 𝑥 ∧ 𝑥 ⊆ 𝑠 ∧ (𝑘 ↾t 𝑠) ∈ 𝐴))) → ((𝑘 ↾t 𝑠) ↾t 𝑥) = (𝑘 ↾t 𝑥))
18 dfss2 3917 . . . . . . . . . . . . . . . 16 (𝑥 ⊆ 𝑠 ↔ (𝑥 ∩ 𝑠) = 𝑥)
196, 18sylib 221 . . . . . . . . . . . . . . 15 (((((𝜑 ∧ 𝑘 ∈ 𝑛-Locally 𝐴) ∧ 𝑦 ∈ 𝑘 ∧ 𝑢 ∈ 𝑦) ∧ 𝑠 ∈ 𝒫 𝑦) ∧ (𝑥 ∈ 𝑘 ∧ (𝑢 ∈ 𝑥 ∧ 𝑥 ⊆ 𝑠 ∧ (𝑘 ↾t 𝑠) ∈ 𝐴))) → (𝑥 ∩ 𝑠) = 𝑥)
20 elrestr 17579 . . . . . . . . . . . . . . . 16 ((𝑘 ∈ Top ∧ 𝑠 ∈ 𝒫 𝑦 ∧ 𝑥 ∈ 𝑘) → (𝑥 ∩ 𝑠) ∈ (𝑘 ↾t 𝑠))
2115, 7, 5, 20syl3anc 1398 . . . . . . . . . . . . . . 15 (((((𝜑 ∧ 𝑘 ∈ 𝑛-Locally 𝐴) ∧ 𝑦 ∈ 𝑘 ∧ 𝑢 ∈ 𝑦) ∧ 𝑠 ∈ 𝒫 𝑦) ∧ (𝑥 ∈ 𝑘 ∧ (𝑢 ∈ 𝑥 ∧ 𝑥 ⊆ 𝑠 ∧ (𝑘 ↾t 𝑠) ∈ 𝐴))) → (𝑥 ∩ 𝑠) ∈ (𝑘 ↾t 𝑠))
2219, 21eqeltrrd 2862 . . . . . . . . . . . . . 14 (((((𝜑 ∧ 𝑘 ∈ 𝑛-Locally 𝐴) ∧ 𝑦 ∈ 𝑘 ∧ 𝑢 ∈ 𝑦) ∧ 𝑠 ∈ 𝒫 𝑦) ∧ (𝑥 ∈ 𝑘 ∧ (𝑢 ∈ 𝑥 ∧ 𝑥 ⊆ 𝑠 ∧ (𝑘 ↾t 𝑠) ∈ 𝐴))) → 𝑥 ∈ (𝑘 ↾t 𝑠))
23 eleq2 2850 . . . . . . . . . . . . . . . 16 (𝑗 = (𝑘 ↾t 𝑠) → (𝑥 ∈ 𝑗 ↔ 𝑥 ∈ (𝑘 ↾t 𝑠)))
24 oveq1 7419 . . . . . . . . . . . . . . . . 17 (𝑗 = (𝑘 ↾t 𝑠) → (𝑗 ↾t 𝑥) = ((𝑘 ↾t 𝑠) ↾t 𝑥))
2524eleq1d 2846 . . . . . . . . . . . . . . . 16 (𝑗 = (𝑘 ↾t 𝑠) → ((𝑗 ↾t 𝑥) ∈ 𝐴 ↔ ((𝑘 ↾t 𝑠) ↾t 𝑥) ∈ 𝐴))
2623, 25imbi12d 347 . . . . . . . . . . . . . . 15 (𝑗 = (𝑘 ↾t 𝑠) → ((𝑥 ∈ 𝑗 → (𝑗 ↾t 𝑥) ∈ 𝐴) ↔ (𝑥 ∈ (𝑘 ↾t 𝑠) → ((𝑘 ↾t 𝑠) ↾t 𝑥) ∈ 𝐴)))
2714simpld 500 . . . . . . . . . . . . . . . 16 (((((𝜑 ∧ 𝑘 ∈ 𝑛-Locally 𝐴) ∧ 𝑦 ∈ 𝑘 ∧ 𝑢 ∈ 𝑦) ∧ 𝑠 ∈ 𝒫 𝑦) ∧ (𝑥 ∈ 𝑘 ∧ (𝑢 ∈ 𝑥 ∧ 𝑥 ⊆ 𝑠 ∧ (𝑘 ↾t 𝑠) ∈ 𝐴))) → 𝜑)
28 restlly.1 . . . . . . . . . . . . . . . . . 18 ((𝜑 ∧ (𝑗 ∈ 𝐴 ∧ 𝑥 ∈ 𝑗)) → (𝑗 ↾t 𝑥) ∈ 𝐴)
2928expr 462 . . . . . . . . . . . . . . . . 17 ((𝜑 ∧ 𝑗 ∈ 𝐴) → (𝑥 ∈ 𝑗 → (𝑗 ↾t 𝑥) ∈ 𝐴))
3029ralrimiva 3155 . . . . . . . . . . . . . . . 16 (𝜑 → ∀𝑗 ∈ 𝐴 (𝑥 ∈ 𝑗 → (𝑗 ↾t 𝑥) ∈ 𝐴))
3127, 30syl 18 . . . . . . . . . . . . . . 15 (((((𝜑 ∧ 𝑘 ∈ 𝑛-Locally 𝐴) ∧ 𝑦 ∈ 𝑘 ∧ 𝑢 ∈ 𝑦) ∧ 𝑠 ∈ 𝒫 𝑦) ∧ (𝑥 ∈ 𝑘 ∧ (𝑢 ∈ 𝑥 ∧ 𝑥 ⊆ 𝑠 ∧ (𝑘 ↾t 𝑠) ∈ 𝐴))) → ∀𝑗 ∈ 𝐴 (𝑥 ∈ 𝑗 → (𝑗 ↾t 𝑥) ∈ 𝐴))
32 simprr3 1242 . . . . . . . . . . . . . . 15 (((((𝜑 ∧ 𝑘 ∈ 𝑛-Locally 𝐴) ∧ 𝑦 ∈ 𝑘 ∧ 𝑢 ∈ 𝑦) ∧ 𝑠 ∈ 𝒫 𝑦) ∧ (𝑥 ∈ 𝑘 ∧ (𝑢 ∈ 𝑥 ∧ 𝑥 ⊆ 𝑠 ∧ (𝑘 ↾t 𝑠) ∈ 𝐴))) → (𝑘 ↾t 𝑠) ∈ 𝐴)
3326, 31, 32rspcdva 3578 . . . . . . . . . . . . . 14 (((((𝜑 ∧ 𝑘 ∈ 𝑛-Locally 𝐴) ∧ 𝑦 ∈ 𝑘 ∧ 𝑢 ∈ 𝑦) ∧ 𝑠 ∈ 𝒫 𝑦) ∧ (𝑥 ∈ 𝑘 ∧ (𝑢 ∈ 𝑥 ∧ 𝑥 ⊆ 𝑠 ∧ (𝑘 ↾t 𝑠) ∈ 𝐴))) → (𝑥 ∈ (𝑘 ↾t 𝑠) → ((𝑘 ↾t 𝑠) ↾t 𝑥) ∈ 𝐴))
3422, 33mpd 16 . . . . . . . . . . . . 13 (((((𝜑 ∧ 𝑘 ∈ 𝑛-Locally 𝐴) ∧ 𝑦 ∈ 𝑘 ∧ 𝑢 ∈ 𝑦) ∧ 𝑠 ∈ 𝒫 𝑦) ∧ (𝑥 ∈ 𝑘 ∧ (𝑢 ∈ 𝑥 ∧ 𝑥 ⊆ 𝑠 ∧ (𝑘 ↾t 𝑠) ∈ 𝐴))) → ((𝑘 ↾t 𝑠) ↾t 𝑥) ∈ 𝐴)
3517, 34eqeltrrd 2862 . . . . . . . . . . . 12 (((((𝜑 ∧ 𝑘 ∈ 𝑛-Locally 𝐴) ∧ 𝑦 ∈ 𝑘 ∧ 𝑢 ∈ 𝑦) ∧ 𝑠 ∈ 𝒫 𝑦) ∧ (𝑥 ∈ 𝑘 ∧ (𝑢 ∈ 𝑥 ∧ 𝑥 ⊆ 𝑠 ∧ (𝑘 ↾t 𝑠) ∈ 𝐴))) → (𝑘 ↾t 𝑥) ∈ 𝐴)
3612, 13, 35jca32 525 . . . . . . . . . . 11 (((((𝜑 ∧ 𝑘 ∈ 𝑛-Locally 𝐴) ∧ 𝑦 ∈ 𝑘 ∧ 𝑢 ∈ 𝑦) ∧ 𝑠 ∈ 𝒫 𝑦) ∧ (𝑥 ∈ 𝑘 ∧ (𝑢 ∈ 𝑥 ∧ 𝑥 ⊆ 𝑠 ∧ (𝑘 ↾t 𝑠) ∈ 𝐴))) → (𝑥 ∈ (𝑘 ∩ 𝒫 𝑦) ∧ (𝑢 ∈ 𝑥 ∧ (𝑘 ↾t 𝑥) ∈ 𝐴)))
3736ex 418 . . . . . . . . . 10 ((((𝜑 ∧ 𝑘 ∈ 𝑛-Locally 𝐴) ∧ 𝑦 ∈ 𝑘 ∧ 𝑢 ∈ 𝑦) ∧ 𝑠 ∈ 𝒫 𝑦) → ((𝑥 ∈ 𝑘 ∧ (𝑢 ∈ 𝑥 ∧ 𝑥 ⊆ 𝑠 ∧ (𝑘 ↾t 𝑠) ∈ 𝐴)) → (𝑥 ∈ (𝑘 ∩ 𝒫 𝑦) ∧ (𝑢 ∈ 𝑥 ∧ (𝑘 ↾t 𝑥) ∈ 𝐴))))
3837reximdv2 3173 . . . . . . . . 9 ((((𝜑 ∧ 𝑘 ∈ 𝑛-Locally 𝐴) ∧ 𝑦 ∈ 𝑘 ∧ 𝑢 ∈ 𝑦) ∧ 𝑠 ∈ 𝒫 𝑦) → (∃𝑥 ∈ 𝑘 (𝑢 ∈ 𝑥 ∧ 𝑥 ⊆ 𝑠 ∧ (𝑘 ↾t 𝑠) ∈ 𝐴) → ∃𝑥 ∈ (𝑘 ∩ 𝒫 𝑦)(𝑢 ∈ 𝑥 ∧ (𝑘 ↾t 𝑥) ∈ 𝐴)))
3938rexlimdva 3164 . . . . . . . 8 (((𝜑 ∧ 𝑘 ∈ 𝑛-Locally 𝐴) ∧ 𝑦 ∈ 𝑘 ∧ 𝑢 ∈ 𝑦) → (∃𝑠 ∈ 𝒫 𝑦∃𝑥 ∈ 𝑘 (𝑢 ∈ 𝑥 ∧ 𝑥 ⊆ 𝑠 ∧ (𝑘 ↾t 𝑠) ∈ 𝐴) → ∃𝑥 ∈ (𝑘 ∩ 𝒫 𝑦)(𝑢 ∈ 𝑥 ∧ (𝑘 ↾t 𝑥) ∈ 𝐴)))
404, 39mpd 16 . . . . . . 7 (((𝜑 ∧ 𝑘 ∈ 𝑛-Locally 𝐴) ∧ 𝑦 ∈ 𝑘 ∧ 𝑢 ∈ 𝑦) → ∃𝑥 ∈ (𝑘 ∩ 𝒫 𝑦)(𝑢 ∈ 𝑥 ∧ (𝑘 ↾t 𝑥) ∈ 𝐴))
41403expb 1138 . . . . . 6 (((𝜑 ∧ 𝑘 ∈ 𝑛-Locally 𝐴) ∧ (𝑦 ∈ 𝑘 ∧ 𝑢 ∈ 𝑦)) → ∃𝑥 ∈ (𝑘 ∩ 𝒫 𝑦)(𝑢 ∈ 𝑥 ∧ (𝑘 ↾t 𝑥) ∈ 𝐴))
4241ralrimivva 3206 . . . . 5 ((𝜑 ∧ 𝑘 ∈ 𝑛-Locally 𝐴) → ∀𝑦 ∈ 𝑘 ∀𝑢 ∈ 𝑦 ∃𝑥 ∈ (𝑘 ∩ 𝒫 𝑦)(𝑢 ∈ 𝑥 ∧ (𝑘 ↾t 𝑥) ∈ 𝐴))
43 islly 23767 . . . . 5 (𝑘 ∈ Locally 𝐴 ↔ (𝑘 ∈ Top ∧ ∀𝑦 ∈ 𝑘 ∀𝑢 ∈ 𝑦 ∃𝑥 ∈ (𝑘 ∩ 𝒫 𝑦)(𝑢 ∈ 𝑥 ∧ (𝑘 ↾t 𝑥) ∈ 𝐴)))
442, 42, 43sylanbrc 595 . . . 4 ((𝜑 ∧ 𝑘 ∈ 𝑛-Locally 𝐴) → 𝑘 ∈ Locally 𝐴)
4544ex 418 . . 3 (𝜑 → (𝑘 ∈ 𝑛-Locally 𝐴 → 𝑘 ∈ Locally 𝐴))
4645ssrdv 3937 . 2 (𝜑 → 𝑛-Locally 𝐴 ⊆ Locally 𝐴)
47 llyssnlly 23777 . . 3 Locally 𝐴 ⊆ 𝑛-Locally 𝐴
4847a1i 11 . 2 (𝜑 → Locally 𝐴 ⊆ 𝑛-Locally 𝐴)
4946, 48eqssd 3948 1 (𝜑 → 𝑛-Locally 𝐴 = Locally 𝐴)
Colors of variables:    wff setvar class
This proof depends on syntax axioms:   → wi 4   ∧ wa 401   ∧ w3a 1103   = wceq 1570   ∈ wcel 2145  ∀wral 3077  ∃wrex 3087   ∩ cin 3898   ⊆ wss 3899  𝒫 cpw 4557  (class class class)co 7412   ↾t crest 17571  Topctop 23191  Locally clly 23763  𝑛-Locally cnlly 23764
This proof depends on axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1828  ax-4 1842  ax-5 1943  ax-6 2000  ax-7 2041  ax-8 2147  ax-9 2155  ax-10 2178  ax-11 2194  ax-12 2213  ax-ext 2733  ax-rep 5232  ax-sep 5249  ax-nul 5260  ax-pow 5327  ax-pr 5391  ax-un 7740
This proof depends on definitions:  df-bi 210  df-an 402  df-or 862  df-3an 1105  df-tru 1573  df-fal 1583  df-ex 1813  df-nf 1817  df-sb 2100  df-mo 2565  df-eu 2595  df-clab 2740  df-cleq 2753  df-clel 2836  df-nfc 2910  df-ne 2957  df-ral 3078  df-rex 3088  df-reu 3367  df-rab 3414  df-v 3453  df-sbc 3740  df-csb 3848  df-dif 3902  df-un 3904  df-in 3906  df-ss 3916  df-nul 4280  df-if 4483  df-pw 4559  df-sn 4585  df-pr 4587  df-op 4591  df-uni 4868  df-iun 4953  df-br 5104  df-opab 5168  df-mpt 5187  df-id 5546  df-xp 5657  df-rel 5658  df-cnv 5659  df-co 5660  df-dm 5661  df-rn 5662  df-res 5663  df-ima 5664  df-iota 6487  df-fun 6533  df-fn 6534  df-f 6535  df-f1 6536  df-fo 6537  df-f1o 6538  df-fv 6539  df-ov 7415  df-oprab 7416  df-mpo 7417  df-rest 17573  df-top 23192  df-nei 23396  df-lly 23765  df-nlly 23766
This theorem is used by:  loclly  23786  hausnlly  23792
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