Confusion regarding limits in computing Fourier transform of a signal involving modulus

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I need to find Fourier transform of

$$\sum_{n=-\infty }^\infty e^{-|t-2n|}$$

I found the solution online. But I think the choice of limits in equation (1) of the solution is wrong.It should be probably from -infinity to 2n for the first integral and from 2n to infinity for the second integral.But I am confused about what the limits would be as the both integration and summation is involved. and I am not sure whose limits to change(Probably limits of integration must be changed only and that of summation must be kept as it is)

Given Solution:

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Please tell me what the limits will be and the explanation. Also if possible please solve the problem.

Original answer:

$$ \frac{(1-e^{-2(1+jw)})}{(1-e^{-2})(1+jw)}-\frac{(e^{-2})(1-e^{-2(1+jw)})}{(1-e^{-2})(1-jw)}$$

OR

Answer:

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