Type error : importing things and doesn't work

Question

Guys can you help please? You see I created a module (if you want to know how get Hello world book 2nd edition) and imported it but the functions don't work. Here are the module and scripts

coin.py

class Coin:
    def flip_coin(self, op):
        a = random.choice(op)
        easygui.msgbox(a) 

script

import random
import easygui
from coin import Coin

op = ["Heads", "Tails"]

easygui.msgbox("Ready?")
Coin.flip_coin()

You guys wanted to see the error:

    Traceback (most recent call last): File "C:\Python27\Hello world\coin", line 9, in <module> flip_coin() TypeError: flip_coin() takes exactly 2 arguments (0 given) 

Answer 1

The problem is (aside from the fact that your question doesn't have the actual error ;-) ) that you haven't instantiated an object of your Coin class, and you don't pass in op.

In addition, since Coin lives in a separate module, it too needs to have random and easygui imported if you use them.

coin.py

import random
import easygui


class Coin:
    def flip_coin(self, op):
        a = random.choice(op)
        easygui.msgbox(a)

script

import easygui
from coin import Coin

coin = Coin()  # instantiate the class

easygui.msgbox("Ready?")
coin.flip_coin(["Heads", "Tails"])

---

However, it's not Pythonic to use a class when you don't actually need to store state.

Instead, you can just leave def flip_coin(op): a free function -- and also, since coins don't usually have more options than heads or tails:

import random
import easygui

def flip_coin():
    a = random.choice(["Heads", "Tails"])
    easygui.msgbox(a) 

easygui.msgbox("Ready?")
flip_coin()