Inverse of sum of matrices rearrangement

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I see this conversion of an inverse in a script and do not understand how this works. Could someone please explain or give me a hint please? Would be so much appreciated.

$R W^T(WRW^T + Q)^{-1}$ = $(W^T Q^{-1} W + R^{-1})^{-1}W^TQ^{-1}$

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We'll use the property $(AB)^{-1} = B^{-1}A^{-1}$ a bit here.

We have: $$\begin{split}&RW^T(WRW^T + Q)^{-1} \\ &= (W^{-T}R^{-1})^{-1}(WRW^{T} + Q)^{-1} \\ &= ((WRW^T+Q)(W^{-T}R^{-1}))^{-1}\\ &= (W+QW^{-T}R^{-1})^{-1}\\ &= (QW^{-T}(W^{T}Q^{-1}W+R^{-1}))^{-1}\\ &= (W^{T}Q^{-1}W+R^{-1})^{-1}(QW^{-T})^{-1}\\ &= (W^{T}Q^{-1}W+R^{-1})^{-1}W^{T}Q^{-1}\\\end{split}$$ Which is what we wanted.