basisList -- gives the list used to label the basis elements of a labeled module

One of the key features of a labeled module of rank $r$ is that the basis can be labeled by any list of cardinality $r$. This is particularly convenient when working with tensor products, symmetric powers, and exterior powers. For instance, if $A$ is a labeled module with basis labeled by $\{0,\dots, r-1\}$ then it is natural to think of $\wedge^2 A$ as a labeled module with a basis labeled by elements of the lists $$ \{(i,j)| 0\leq i<j\leq r-1\}. $$ When you use apply the functions tensorProduct, symmetricPower and exteriorPower to a labeled module, the output is a labeled module with a natural basis list.