What function $I_{Q}(\omega)$ represents?

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I am working on CDF calculation questions, but got one specific example where I am not sure what function $I_{Q}(\omega)$ represents?

Ive tried to google but its not easy as I dont know name of this function.

Example:

Consider the probability space $(\mathbb{R},\mathcal{B}(\mathbb{R}),\mathbb{P})$, where $\mathbb{P}=0.1\delta_{-2\pi}+0.7\delta_1+0.2\delta_{\sqrt{2}}.$

If $X(\omega)=I_{Q}(\omega)$, then the CDF of X is?