input: 
  def create_store_item_instance(item_id, name, price, description):
      """Create an instance of the StoreItem class with the given parameters and return it.
      >>> item = create_store_item_instance(1, 'Book', 10.99, 'A fascinating read')
      >>> print(item)
      Book, $10.99
      >>> item.to_dict()
      {'item_id': 1, 'name': 'Book', 'price': 10.99, 'description': 'A fascinating read'}
      """
      class StoreItem:
          def __init__(self, item_id, name, price, description):
              self.item_id = item_id
              self.name = name
              self.price = price
              self.description = description
  
          def __str__(self):
              return f'{self.name}, ${self.price}'
  
          def to_dict(self):
              return {
                  'item_id': self.item_id,
                  'name': self.name,
                  'price': self.price,
                  'description': self.description
              }
      return StoreItem(item_id, name, price, description)
  
output:     return StoreItem(item_id, name, price, description)