input: Write a function to create a Python generator that returns numbers from a given list. If the list is empty, the generator should return an empty sequence.
  def list_generator(input_list):
      for item in input_list:
          yield item
  
  assert list(list_generator([1,3,5,7,9]))==[1,3,5,7,9]
  assert list(list_generator([]))==[]
output: def list_generator(input_list):
      for item in input_list:
          yield item