A modification of inclusion-exclusion formula.

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Let $S=\{1,2,...m\}$

And $A_{1},...,A_m\subseteq X$ be some sets

$\mu:\mathcal{P}(X)\rightarrow \mathbb{C}$

Let also

$$F(S):=\sum_{I\subseteq S}(-1)^{|I|-1}\mu(\bigcap_{i\in I}A_{i})$$

If function $\mu$ is a measure then: $$F(S)=\mu(\bigcup_{i\in S}A_i)$$

This is inclusion-exclusion formula.

But what if we consider another set $Z\subseteq S$ and following expressions:

$$H(S, Z) = \sum_{I\subseteq S-Z}(-1)^{|I|-1}\mu(\bigcap_{i\in I\cup Z}A_{i}) = \sum_{I:Z\subseteq I \subseteq S}(-1)^{|I|-1}\mu(\bigcap_{i\in I}A_{i})$$

$$G(S, Z) = \sum_{I:Z\subseteq I \subseteq S}\mu(\bigcap_{i\in I}A_{i})$$

Find formulas for $G, H$

Thank you in advance.

EDIT:

Generally i am intrested in formula for:

$$\sum_{Z\subseteq I\subseteq S}\prod_{T\subseteq I}f(T)$$ where all the $T$ have fixed size $|T|=a$ and $|Z|+1\le a$

Particularly i would like to calculate: $$\sum_{\{x\}\subseteq I\subseteq S}\prod_{\{a_1,a_2\}\subseteq I}f(\{a_1,a_2\})$$