Only using lisp, and no builtin functions can be used except the basic ones like cons car cdr defun append if

Write the Lisp function: (allsubsets L) Examples that returns a list of all subsets of L. How the subsets in the resulting list are ordered is unimportant. Hint: Use an accumulator to accumulate all subsets of L, e.g., as (defun allsubsets (L) (gen-subsets (cons nil nil) L)) where the first parameter for gen-subsets is an accumulator that starts with an empty set, which is a subset of any set Write the Lisp function: (allsubsets L) Examples that returns a list of all subsets of L. How the subsets in the resulting list are ordered is unimportant. Hint: Use an accumulator to accumulate all subsets of L, e.g., as (defun allsubsets (L) (gen-subsets (cons nil nil) L)) where the first parameter for gen-subsets is an accumulator that starts with an empty set, which is a subset of any set