input: Write a function to improve the Python code for finding the sum of elements of a list by using a more efficient method. The function should be able to handle empty lists and return 0 in such cases.
  
  assert sum_elements([1, 2, 3, 4, 5])==15
  assert sum_elements([10, 20, 30])==60
  assert sum_elements([-1, -2, -3, -4, -5])==-15
  assert sum_elements([])==0
output: def sum_elements(lst):
      return sum(lst)