input: Write a function that improves the given Python code for summing elements of a list. The improved function should achieve the same result using a more efficient or cleaner approach.
  assert sum_elements([1, 2, 3, 4, 5])==15
  assert sum_elements([10, 20, 30])==60
  assert sum_elements([0, -1, 1])==0
  assert sum_elements([])==0
output: def sum_elements(lst):
      return sum(lst)