Can someone please explain the following definition of $\ln(e^z)$

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I noticed someone do this from one of the questions is asked on here i had:

$$e^z = -0.5$$

$$e^z = 0.5e^{i\pi}$$

which magically became:

$$z = \ln\left(\frac12\right) + iπ + 2ikπ$$

does this mean that if i have:

$$e^z = -r = re^{i\pi} = \ln(r) + iπ + 2ikπ$$

Thanks for any help you can offer me, i have really been strugling with this,

edit:

Oh my bad i meant to write:

$$e^z = -r = re^{i\pi} = \ln|r| + iπ + 2ikπ$$

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Let $r \in R$ and let $z \in C$, where $e^{z}=-r$. Since $e^{i\pi}=-1$ and $e^{2i\pi}=1$, it follows that $e^{z}=e^{z}\cdot (1)^k=e^z\cdot (e^{2i\pi})^k=e^{z}\cdot e^{2ki\pi}=r\cdot(-1)=r\cdot e^{i\pi}$ where $k\in Z$. Now taking the logarithm of both sides of the equation $e^{z} \cdot e^{2ki\pi}=r\cdot e^{i\pi}$, we have that $ln(e^{z} \cdot e^{2ki\pi})=ln(r\cdot e^{i\pi})$. So $z+2ki\pi =ln(r)+i\pi$ and thus $z=ln(r)+i\pi-2ki\pi$. Since k is an arbitrary integer, we can rewrite this expression as $z=ln(r)+i\pi+2ki\pi$. Hope this helps.