Check if an item is in the bag using json (economy system bot

This is the code for my "bag" or inventory command

async def bag(ctx):
    await open_account(
    user =
    users = await get_bank_data()
        bag = users[str(]["bag"]
        bag = []

    em = discord.Embed(title = "Bag")
    for item in bag:
        name = item["item"]
        amount = item["amount"]

        em.add_field(name = name, value = amount)    

    await ctx.send(embed = em)

So i want to check if there is a specific item in the bag. Suppose the item name is "common", how would i do that? Ive tried numerous for item in bag and stuff like that but none work!