from math import *
from tkinter import *

f = "7**(2 * x + 1)"
root = Tk()

canv = Canvas(root, width=1000, height=1000, bg="white")
canv.create_line(500, 1000, 500, 0, width=2, arrow=LAST)
canv.create_line(0, 500, 1000, 500, width=2, arrow=LAST)

First_x = -500

for i in range(32000):
    if i % 800 == 0:
        k = First_x + (1 / 16) * i
        canv.create_line(k + 500, -3 + 500, k + 500, 3 + 500, width = 0.5, fill = 'black')
        canv.create_text(k + 515, -10 + 500, text = str(k), fill="purple", font=("Helvectica", "10"))
        if k != 0:
            canv.create_line(-3 + 500, k + 500, 3 + 500, k + 500, width = 0.5, fill = 'black')
            canv.create_text(20 + 500, k + 500, text = str(k), fill="purple", font=("Helvectica", "10"))
    try:
        x = First_x + i/8
        new_f = f.replace('x', str(x))
        y = -eval(new_f) + 500
        x += 500
        canv.create_oval(x, y, x + 1, y + 1, fill = 'orange')
    except:
        pass
canv.pack()
root.mainloop()