**Input:** None.

**Goal:** Return the inverse of the following matrix:

$$\begin{bmatrix} 1 & 2 \\ 3 & 4 \end{bmatrix}$$

:::hint
You can check out [this Wikipedia article](https://en.wikipedia.org/wiki/Invertible_matrix#Inversion_of_2_%C3%97_2_matrices) about invertible matrices.
:::
