Please I need help finding a simple function that meets Cauchy Riemann at z=0 but is not differentiable at that point. This is all I can find. Can you talk about this topic in simple terms: a function that meets Cauchy Riemann at z=0 but is not differentiable at that point and explain why a function like below is not differentiable at z=0 but meet Cauchy Riemann at z=0. Please simple explanation. Thank you.

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