Inverse of a function of a 3rd order

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can someone help me how to find the inverse the following function?

$$z(\zeta)=\frac{1}{\zeta}+m_1\zeta+m_2\zeta^2+m_3\zeta^3$$

In my case, $z$ is a complex number and cannot be zero. And $m_k$ is a constant.

How do I get the inverse of that function? i.e. I want to express $\zeta(z)$? IS it possible to have an explicit formulation? Or, for a given $z$ can we solved $\zeta(z)$ numerically?

Example

Consider the following function: $$z(\zeta)=\frac{1}{\zeta}$$

In my understanding, the inverse of the above function is $$\zeta(z)=\frac{1}{z}$$

Your help is highly appreciated.

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The answer of this question has be given by @nathan.j.mcdougall above. It is essentially solving numerically the following equation

$$m_3\zeta^4+m_2\zeta^3+m_1\zeta^2−z\zeta+1=0$$