# Last in list
#  99 Problems, #1: last in list
# Write a function last that accepts a list and returns the last element in the list.
# If the list is empty:
# In languages that have a built-in option or result type (like OCaml or Haskell), return an empty option
# In languages that do not have an empty option, just return None
def last(lst):
    if lst == []:return None
    else:return lst[-1]gi