How do avoid the global statement in python

1

I am completely new to python (know C, C++ and Delphi).
I have coded this little example (code last in message), trying to learn python.

It should (and does) open a window 500x500 with a counter in the upper left corner, current date and time in the lower left corner and the current window size in the lower right corner.

So far so good.

When I check my code with Pylint it gives me:

C0103:invalid-name: 14,0: Constant name “tic” doesn’t conform to UPPER_CASE naming style

C0103:invalid-name: 19,4: Constant name “tic” doesn’t conform to UPPER_CASE naming style

W0603:global-statement: 19,4: Using the global statement

How do I avoid these messages?

I mean “tic” is not a constant it is a variable.

I would really like to avoid the global statement, but then I get an error saying that “tic” does not exist.

I am sure it is because I do not know how to code in python properly.

Anyone that can help me a little bit?

Thank in advance.

# -*- coding: utf-8 -*-
"""
Created on Wed Aug 10 08:01:10 2022

@author: LAC
"""

import tkinter as tk
import time

CANVAS_WIDTH = 500
CANVAS_HEIGHT = 500

tic = 0


def func_1():
    """ func_1 """
    global tic
    tic += 1
    label_1["text"] = str(tic)
    canvas.after(100, func_1)


def func_2(event):
    """ func_2 """
    label_2["text"] = "Test " + str(event.width) + " " + str(event.height)


def func_3():
    """ func_3 """
    _t = time.localtime()
    _ts = time.strftime("%Y-%m-%d %H:%M:%S", _t)
    label_3["text"] = _ts
    canvas.after(500, func_3)


if __name__ == "__main__":
    master = tk.Tk()
    master.title("Points")

    canvas = tk.Canvas(master, width=CANVAS_WIDTH, height=CANVAS_HEIGHT)
    canvas.pack(expand=tk.YES, fill=tk.BOTH)

    label_1 = tk.Label(master, text="label_1")
    canvas.create_window(0, 0, window=label_1)
    label_1.place(relx=0, rely=0, anchor="nw")

    label_2 = tk.Label(master, text="label_2")
    canvas.create_window(0, 0, window=label_2)
    label_2.place(relx=1.00, rely=1.00, anchor="se")

    label_3 = tk.Label(master, text="label_3")
    canvas.create_window(0, 0, window=label_3)
    label_3.place(relx=0.00, rely=1.00, anchor="sw")

    func_1()

    func_3()

    canvas.bind("", func_2)

    master.mainloop()
2

I am also learning python.
Try moving the variable tic to one of your functions and declaring it like this

global tic = 0

(Make sure to remove the line tic = 0 outside the function though)

3

Another thing I learned answering this question: The interpreter thinks you are making conflicting definitions as when you put a variable definition outside a function you are essentially saying it is a constant. Then later you try to change its definition with the use of the keyword global. And so that is a conflict.

If you need a glabal variable that you can write to, define it inside a function but with the addition of the word global added to it.
(I know, weird right?)

Hope It works for you.

4

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