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Say U is a list of things and F is a list of forbidden things.

We want to check that none of the forbidden things is in U.

One way to perform such a check is as follows:

sage: all(a not in U for a in F)

Say U is a list of things permutations and F is a list of forbidden things.patterns.

We want to check that none of the all permutations in U avoid all forbidden things is in U.patterns.

One way to perform such a check is as follows:

sage: all(a not in U for a in F)
U = [[2, 3, 1, 4, 5], [2, 4, 1, 3, 5], [2, 5, 1, 3, 4], [2, 1, 3, 4, 5],
....:      [1, 3, 4, 2, 5], [1, 3, 5, 2, 4], [1, 3, 2, 4, 5], [3, 1, 4, 2, 5],
....:      [3, 4, 1, 2, 5], [3, 5, 1, 2, 4], [3, 1, 2, 4, 5], [1, 2, 4, 5, 3],
....:      [1, 2, 4, 3, 5], [1, 4, 2, 5, 3], [1, 4, 5, 2, 3], [1, 4, 2, 3, 5],
....:      [4, 1, 2, 5, 3], [4, 1, 5, 2, 3], [4, 5, 1, 2, 3], [4, 1, 2, 3, 5],
....:      [1, 2, 3, 5, 4], [1, 2, 5, 3, 4], [1, 5, 2, 3, 4], [5, 1, 2, 3, 4],
....:      [1, 2, 3, 4, 5]]
sage: F = [[3, 1, 2, 4], [4, 1, 2, 3]]

sage: U = [Permutation(p) for p in U]
sage: F = [Permutation(p) for p in F]

sage: all(u.avoids(f) for f in F for u in U)