def is_solved(neighbours, colors):
    """Checks for all countries, if all their neighbours have another color.

    :param neighbours: A dict with country as keys, list of neighbours as values
    :param colors: A list indicating which country has which color. First element in this list corresponds
    to color of first country
    :return: Boolean
    """
    if None in colors:
        return False
    elif len(neighbours) != len(colors):
        return False

    for country in neighbours:
        color = colors[country]
        for neighbour in neighbours[country]:
            if colors[neighbour] == color:
                return False
    return True