rainbow.py

from itertools import cycle
from colorama import Fore, Back, Style, init as colorama_init
colorama_init()

def clear():
    from os import system, name

    if name == 'nt':
        system('cls')
    else:
        system('clear')

class Widget:
    _fore = Fore.WHITE
    _back = Back.BLACK
    _style = Style.NORMAL

    def __init__(self, x, y, size, fore=None, back=None, style=None):
        self.x = x
        self.y = y
        self.size = size
        self.fore = fore if fore else Fore.WHITE
        self.back = back if back else Back.BLACK
        self.style = style if style else Style.NORMAL

    def text(self, msg):
        print("\033[%d;%dH" % (self.y, self.x), end='')
        if Widget._back != self.back:
            print(self.back, end='')
            Widget._back = self.back
        if Widget._fore != self.fore:
            print(self.fore, end='')
            Widget._fore = self.fore
        if Widget._style != self.style:
            print(self.style, end='')
            Widget._style = self.style

        print(f'{msg:<{self.size}}', end='')

backs = cycle([
    Back.BLACK, Back.RED, Back.GREEN, Back.YELLOW,
    Back.BLUE, Back.MAGENTA, Back.CYAN, Back.WHITE
])

widgets = []

clear()
for x in range(25):
    widgets.append([])
    for y in range(20):
        widgets[x].append(Widget(x * 2 + 1, y + 1, 2))

i = 0
while True:
    i += 1
    for x in range(25):
        back = next(backs)
        for y in range(20):
            widgets[x][y].back = back
            widgets[x][y].text('')