Generating ideal from variety (vanishing ideal)

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Hey all,

Is there a fast way to generate an ideal from a variety in Sage? I would like to have something of the form: I = ideal(V), where V is a variety described by a dictionary.

To put it into perspective: I have a set of polynomials P, and I generate ideal J = ideal(P). Next I define variety V = J.variety(), but now I would like to find the vanishing ideal I(V) (under the assumption J is zero-dimensional).

Thank you!