[Python] Calculate cumulative sum from last non-zero entry in python

I have a numeric series like [0,0,0,0,1,1,1,0,0,1,1,0]. I would like to calculate the numeric sum from the last non-zero values. i.e the cumsum will be reset to zero once a zero entry occurs.

input: [0,0,0,0,1,1,1,0,0,1,1,0]
output:[0,0,0,0,1,2,3,0,0,1,2,0]


Is there a built-in python function able to achieve this? Or better way to calculate it without loop?

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