This is a key for a LieAlgebra L, which can be seen by applying peekLie to L.
i1 : L=lieAlgebra{a,b,c}/{a b, a a b - b b c} o1 = L o1 : LieAlgebra
i2 : L.relsLie o2 = { - (b a), - (a b a) + (b c b)} o2 : List
The object relsLie is a symbol.