Serre's theorem on affineness

In algebraic geometry, given an algebraic variety (or more generally scheme) X, Serre's theorem on affineness, after Jean-Pierre Serre, states that if

(1) X is quasi-compact, and
(2) for every quasi-coherent ideal sheaf I of OX, \( H^1(X, I) = 0, \)

then X is affine.
References

http://stacks.math.columbia.edu/tag/01XF

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