The concept of (f, σ)-pair (B,H)is introduced, where B and H are Hopf algebras. A braided tensor category which is a tensor subcategory of the category H\documentclass[12pt]{minimal}
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\mathcal{M}
$$\end{document} of left H-comodules through an (f, σ)-pair is constructed. In particularly, a Yang-Baxter equation is got. A Hopf algebra is constructed as well in the Yetter-Drinfel’d category HH\documentclass[12pt]{minimal}
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\mathcal{Y}\mathcal{D}
$$\end{document} by twisting the multiplication of B.