Python Dictionary Check if Key Exists

Question

@commands.command(aliases=['lookup'])
    async def define(self, message, *, arg):
        dictionary=PyDictionary()
        Define = dictionary.meaning(arg)
        length = len(arg.split())
        if length == 1:
            embed = discord.Embed(description="**Noun:** " + Define["Noun"][0] + "\n\n**Verb:** " + Define["Verb"][0], color=0x00ff00)
            embed.set_author(name = ('Defenition of the word: ' + arg),
            icon_url=message.author.avatar_url)
            await message.send(embed=embed)
        else:
            CommandError = discord.Embed(description= "A Term must be only a single word" , color=0xfc0328)
            await message.channel.send(embed=CommandError)

I want to do check if Noun and Verb is in the dictionary Define, because when a word only has lets say a Noun in its definition then it throws an error because I am trying to bot output the Noun and Verb, see what I am getting at. I am new to dictionaries and any help is much appreciated

`if value in my_dict`. If you'r enew to dictionaries, then your first recourse is to repeat a tutorial on dicts. — Prune, Aug 20 '20 at 05:16

score 13 · Answer 1 · answered Aug 20 '20 at 05:16

13

You can test if key exists with the following code:

if key_to_test in dict.keys():
   print("The key exists")
else:
   print("The key doesn't exist")

answered Aug 20 '20 at 05:16

Raida

1,206
5
17

yes this would work but what would I do if a word has both Verb and Noun, the code would not work – Dan A Aug 20 '20 at 05:20
3

Do a `if noun or verb in dict.keys()` or if it needs both do `if noun and verb in dict.keys()` – Moritz Schmid Aug 20 '20 at 06:20
what? that wouldn’t work – schuelermine May 12 '23 at 21:41
It should be `if (noun or verb) in dict` or `if (noun and verb) in dict`. I just test it and it is working on python3.10 – Raida May 13 '23 at 08:59

score 1 · Accepted Answer · answered Aug 20 '20 at 05:21

Let's note up front that in python a 'dictionary' is a data structure. You're using a third-party library to perform dictionary lookups (as in lexical meanings).

You also need to know how to tell if a python dictionary data structure contains a key. Keep these uses of the word 'dictionary' separate in your mind or you will rapidly get confused. In most python contexts people will assume 'dictionary' means the data structure, not a lexical dictionary like Webster's.

from PyDictionary import PyDictionary

dictionary=PyDictionary()

meanings = dictionary.meaning("test")

if 'Noun' in meanings and 'Verb' in meanings:
    #do everything
elif 'Noun' in meanings:
    #do something
elif 'Verb' in meanings:
    #do something else

score 0 · Answer 3 · answered Aug 20 '20 at 06:02

embed = discord.Embed(description="**Noun:** " + Define["Noun"][0] + "\n\n**Verb:** " + Define["Verb"][0], color=0x00ff00)

You change it to

description = []
if "Noun" in Define:
    description.append("**Noun:** " + Define["Noun"][0])
if "Verb" in Define:
    description.append("**Verb:** " + Define["Verb"][0])

if description:
    embed = discord.Embed(description="\n\n".join(description),
                          color=0x00ff00)
else:
    # DO SOMETHING ELSE IF IT WAS NOT NOUN OR VERB

Python Dictionary Check if Key Exists

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