Python def not changing values of integers

I made a def which is supposed to add 1 to an integer, but it doesn’t.

import ssd1306
import machine
from machine import Pin
import time
import uos
import machine

ez = 0
r = 0
e = 8
nah = 10
erg = 10

WIDTH = 128
HEIGHT = 64
i2c = machine.I2C(0)

def ereter(ez, r, e):
    ez+=1
    print(ez)
    oled.fill(0)
    oled.text("{}".format(ez), 35, 10)
    oled.text(":{}".format(r), 50, 10)
    oled.text(":{}".format(e), 72, 10)
    oled.text("The time is ^ rn", 0, 30)
    oled.text("i2c devices:"+str(i2c.scan()), 0, 40)
    oled.show()
    if ez>58: r+=1
    if ez>58: ez-=60
    if r>58: e+=1
    if r>58: r-=60
    if e>11: e-=12

while nah>1:
    ereter(ez, r, e)
    time.sleep(1)

I was expecting the code to add 1 to ez every second, but instead, it just doesn’t change the value of ez.

>Solution :

You know inside functions all global variables (variables that is defined above after modules) are rewrited. To solve this problem maybe you should add global key after def key. It should look like this:

def ereter(ez, r, e):
    global ez
    ez+=1
    # continue of function