如何从python中的字典中选择一个特定的值

Question

我试图从用户输入项目名称的url中获取一个特定值，并且需要找到项目编号，我不知道如何编写命令。 我是python和dict的新手。

import discord
from discord.ext import commands
import requests
import json


class Test:
    def __init__(self, bot):
        self.bot = bot

    @commands.command()
    @commands.has_any_role("Admin","Moderator")
    async def it(self, ctx , *, name):
        test = await self.bot.pg_con.fetchval("SELECT name FROM item WHERE name = $1", name)
        if name != "None":
            user = await self.bot.pg_con.fetchval("SELECT item_id FROM item where LOWER(name)= $1 ", name)

            if user is not None:
                with open(r'.\\cogs\config.json','r') as json_file:
                    data = json.load(json_file)
                    key = data["key"]
                    url = "https://api.torn.com/torn/" f"{user}" "?selections=items&key=" f"{key}"
                    data = requests.get(url).text
                    dict = json.loads(data)
                    print(dict)
                    name1 = dict['items'][user]['name']
                    print(name1)
                    weapon = dict['items'][user]['type']
                    description = dict['items'][user]['description']
                    market = dict['items'][user]['market_value']
                    buy = dict['items'][user]['buy_price']
                    sell = dict['items'][user]['sell_price']

                    embed = discord.Embed(title=f"{name1}",description=f"{description}",colour=discord.Color.dark_blue())
                    embed.set_footer(text=ctx.author.name,icon_url=ctx.author.avatar_url)
                    embed.add_field(name="Type", value="{}".format(weapon),inline=False)
                    embed.add_field(name="Market Value",value=f"$""{}".format(market),inline=True)
                    embed.add_field(name="Torn Buy Price",value=f"$""{}".format(buy),inline=True)
                    embed.add_field(name="Torn Sell Price",value=f"$""{}".format(sell),inline=True)

                    await ctx.send(embed=embed)
            else:
                await ctx.send("BAN Laz! Ban Laz!")
                with open(r'.\\cogs\config.json', 'r') as json_file:
                    data = json.load(json_file)
                    key = data["key"]
                    url = "https://api.torn.com/torn/?selections=items&key=" f"{key}"
                    data = requests.get(url).text
                    dict = json.loads(data)

用户输入的数据是锤子，我需要从下面的信息中选择1。

{"items":{"1":{"name":"Hammer",
               "description":"A small, lightweight tool used in the building industry. Can also be used as a weapon.", 
               "type":"Melee", 
               "buy_price":75, "sell_price":50, "market_value":74,
               "circulation":1282843,
               "image":"https:\/\/www.torn.com\/images\/items\/1\/large.png"}
}}

我试图让它工作，但没有成功。 我得到类型错误：str对象不可调用。 我可能在某种程度上没有做正确的事情。

            with open(r'.\\cogs\config.json', 'r') as json_file:
                data = json.load(json_file)
                key = data["key"]
                url = "https://api.torn.com/torn/?selections=items&key=" f"{key}"
                data = requests.get(url).text
                my_dict = json.loads(data)
                item_found = None
                for index, my_dict in data():
                    # index gets '1', item_dict gets the rest
                    if my_dict['name']: "removed = keyword" because it needed a colon. 
                        item_found = index
                        break
                return item_found   

Answer 1

如果您知道关键字（Hammer）是键'name'下的值，那么您可以迭代这些项。

item_found = None
for index, item_dict in data.items():
   # index gets '1', item_dict gets the rest
   if item_dict['name'] = keyword:
      item_found = index
      break
return item_found

您还可以尝试列表推导：

item_list = [key for (key, value) in data.items() if value == keyword]

这将返回一个项目列表。 在正常情况下，输入数据字典将具有多个项目，并且可能存在多个锤子。