This is the line of code with the error:

number = await self.client.wait_for("message", check=lambda m: m.author == ctx.author and m.channel == ctx.channel, timeout=20.0)

This line is inside a 'Shop' class that looks like this:

class Shop(commands.Cog, name="Shop"):
    """asks for a number of how much to buy"""

   def __init__(self, bot: commands.Bot):
    self.bot = bot

   # That line of code is somewhere here

def setup(bot: commands.Bot):
    bot.add_cog(Shop(bot))  

The full error looks like this:

number = await self.client.wait_for("message", check=lambda m: m.author == ctx.author and m.channel == ctx.channel, timeout=20.0)
AttributeError: 'Shop' object has no attribute 'client'

I am dealing with cogs for the first time so it makes sense that I encountered so many errors. But this error specifically hung me for a very long time and I do not no what I should do

I tried:

number = await client.wait_for("message", check=lambda m: # and so on..)

number = await Bot.wait_for("message", check=lambda m: # and so on..)

number = await self.client.wait_for("message", check=lambda m: # and so on..)

And non of them worked for me... This is dealing with discord.py and I am developing a bot with the command "Shop" that asks for input (a number) with "wait_for" and it stores it in the variable "number" so that I can use it in the rest of the command. Would appreciate some help, Thanks -