check condition for a list of lists

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I have a list of lists L = [L1, L2, L3,... Lm] where each Li is a list again. I want to check each Li for a condition.

I need only those Li where all elements of Li satisfy a certain property.

I am trying the following but it's not working the way I want.

for i in range(0, len(L)): U = L[i] for s in U: check(s) But this does not distinguish between the elements of Li.

A little help is needed.

Thanks