input: Write a function to provide an improved version of the given Python code for finding the sum of elements in a list. The improved function should be more concise and efficient.
  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
  assert sum_elements([7])==7
output: def sum_elements(lst):
      return sum(lst)