input: 
  
  def get_positive(l: list):
      """Return only positive numbers in the list.
      >>> get_positive([-1, 2, -4, 5, 6])
      [2, 5, 6]
      >>> get_positive([5, 3, -5, 2, -3, 3, 9, 0, 123, 1, -10])
      [5, 3, 2, 3, 9, 123, 1]
      """
  
output:     return [x for x in l if x > 0]