def rgb_to_hex(color_RGB):
    """Takes a sequence of 3 elements (each one a integer from 0 to 255), representing a RGB color.
    Returns the HTML representation of the color (hexadecimal): #RRGGBB
    """

    color_hex = hex((color_RGB[0] << 16) | (color_RGB[1] << 8) | (color_RGB[2]))    # Convert the color values to hexadecimal
    color_hex = color_hex.replace("0x", "", 1)  # Remove the "0x" from the beginning
    color_hex = color_hex.rjust(6, "0")         # Ensure that the string is 6 characters long (fill with leading "0", if needed)
    color_hex = "#" + color_hex                 # Add a "#" to the beginning

    return color_hex