Python 3.5 class variables

Question

I'm new to python, and I'm using python 3.5 on Ubuntu. I did some research about this question and i found a lot of answers. What I'm doing looks like what everyone is saying I'm supposed to do, but I'm still receiving errors.

import csv
import sys

Class State():
    started = False

    def waiting(self):
        self.started
        if self.started == False:
            self.started = True
        return

    def buy_in(self, col):
        if self.started == False:
            return
        else:
            print(col)

def read_file(file):
    csv_list = csv.reader(file)
    header = True

    for row in csv_list:
        if header:
            header =  False
            continue

        col = float(row[5])

        if col < 0 :
            State.waiting()
        if col >= 0:
            State.buy_in(col)
    file.close()

def main(filename):
    file = open(filename)
    read_file(file)

def __name__ == '__main__':
    main(sys.argv[1])

I'm just trying to create a pseudo FSM in python, by using a class and methods. I just need to create a global bool. I don't really understand what I'm doing wrong. IF someone doesn't mind giving me some clarity, I would appreciate it. Thanks

To clarify, I'm getting the NameError on the if statement in the buy_in method.

Answer 1

Try:

class State():

    started = False

    def waiting(self):
        if self.started == False:
            self.started = True
        return

    def buy_in(self, col):
        if self.started == False:
            return
        else:
            print(col)

Since started is a class variable you need to use self. when calling it. It is not a global variable so you do not need the global call. Each of the methods inside of the class also needs self as an argument.