input: Write a function to check if an element exists within a given list of integers. The function should return True if the element exists in the list or False if it does not. If the given list is empty, it should return False.
  assert element_exists(4, [1, 2, 3, 4])==True
  assert element_exists(4, [1, 2, 3])==False
  assert element_exists(4, [])==False
output: def element_exists(element, lst):
      return element in lst