-Another simple fusion category is the Ising category, commonly denoted $\mathsf{Ising}$. 3 simple objects form this category, namely $\{1, \psi, \sigma\}$, where $1$ and $\psi$ behave like the trivial charged representations of $\mathbb{Z}_2$, while $\sigma$ is the $\mathbb{Z}_2$ extension of this. The fusion rules reflect these: $1 \otimes \psi = \psi = \psi \otimes 1, \sigma \otimes X = \sigma = X \otimes \sigma$ for $X = 1, \psi$, and $\sigma \otimes \sigma = 1 \oplus \psi$. This fusion category is also **modular**. Both these modular fusion categories are already implemented in TensorKit.
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