input: Write a function to check if a list has at least two elements.
  assert has_two_elements([1, 2, 3]) == True
  assert has_two_elements([1]) == False
  assert has_two_elements([]) == False
  assert has_two_elements(['a', 'b']) == True
output: def has_two_elements(lst):
      return len(lst) >= 2