input: Write a function to generate a Python class for an online store item that includes fields for ID, name, price, and description. The class should include an initializer method (__init__) to set these fields, a __str__ method to return a string representation of the item showing the name and price, and a to_dict method to return a dictionary representation of the item.
  
  
  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
          }
  
  assert str(StoreItem(1, "Book", 10.99, "A great book")) == "Book, $10.99"
  assert StoreItem(2, "Pen", 1.99, "A nice pen").to_dict() == {'item_id': 2, 'name': "Pen", 'price': 1.99, 'description': "A nice pen"}
  
output: 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
          }