Change of a polynomial to a list of monomials in sagemath.

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How to change a polynomial to a list of monomials in sagemath? The task is as follows. I defined a set of symbols:

for i in range(k):
    for j in range(n):
        var('y'+'_'+str(i)+'_'+str(j))

I would like to change a polynomial in $y_{ij}$ to a list of monomials. For example,

-y_0_3^2*y_1_2*y_2_1 + y_0_2*y_1_3*y_2_1^3

is changed to [[-1, y_0_3, y_0_3, y_1_2, y_2_1], [1, y_0_2, y_1_3, y_2_1, y_2_1, y_2_1]]. How to do this in sagemath? Thank you very much.