Colouring ASCII art in python

welcome.py

# use color ANSI escape sequences on windows
if os.name == "nt":
    import colorama
    colorama.init()

def welcome():
    BLACK   = "\033[0;30m"
    RED     = "\033[0;31m"
    GREEN   = "\033[0;32m"
    YELLOW  = "\033[0;33m"
    BLUE    = "\033[0;34m"
    MAGENTA = "\033[0;35m"
    CYAN    = "\033[0;36m"
    WHITE   = "\033[0;37m"
    RESET   = "\033[0;0m"
    BOLD    = "\033[;1m"
    def bold(c):
        return c.replace("[0", "[1")

    # http://patorjk.com/software/taag/#p=display&h=3&v=0&f=Graffiti&t=Bunker5%0A
    # modified manually
    b5art = r"""
     __________              __                 ________         ________ ___         ______________________________
     \______   \__ __  ____ |  | __ ___________|   ____/        /  _____/|   |        \______   \_   ____\__    ___/
      |    |  _/  |  \/    \|  |/ // __ \_  __ \____  \        /   \  ___|   |  ______ |    |  _/    \     |    |
      |    |   \  |  /   |  \    <\  ___/|  | \/       \       \    \_\  |   | /_____/ |    |   \     \____|    |
      |________/____/|___|__/__|__\\____\|__| /________/        \________|___|         |________/\________/|____|
    """

    b5art_color = r"""
    C__________              __               G ________      M  ________ ___        M______________________________
    C\______   \__ __  ____ |  | __ __________G|   ____/      M /  _____/|   |       M\______   \_   ____\__    ___/
    C |    |  _/  |  \/    \|  |/ // __ \_  __G\____  \       M/   \  ___|   |C ______M|    |  _/    \     |    |
    C |    |   \  |  /   |  \    <\  ___/|  | G/       \      M\    \_\  |   |C/_____/M|    |   \     \____|    |
    C |________/____/|___|__/__|__\\____\|__|G/________/      M \________|___|        M|________/\________/|____|
    """

    for line, cline in zip(b5art, b5art_color):
        for c, colour in zip(line, cline):
            print(c, end="")
            cd = {"C": CYAN, "M": MAGENTA, "G": GREEN, "Y": YELLOW}
            if colour in cd.keys():
                print(bold(cd[colour]), end="")

    print(RESET)
    print()