input: from typing import List
  
  def element_exists(elem: int, list_int: List[int]) -> bool:
      """ Check if an element exists within a given list of integers.
      >>> element_exists(5, [1, 2, 3, 4, 5])
      True
      >>> element_exists(10, [1, 2, 3, 4, 5])
      False
      >>> element_exists(0, [])
      False
      """
output:     return elem in list_int