def violate_safety_requirement(complete_solution):
    """Checks whether a complete_solution violates a safety requirement. In
    case of violation, the function returns `True`, otherwise it returns
    `False`. Since the definition of fitness function is based on the safety
    requirement and it is defined in a way that its positive sign indicates a
    violation and vice versa.

    :param complete_solution: a complete solution that has a fitness
                              value.
    """
    assert complete_solution is not None, \
        "complete_solution cannot be None."

    assert complete_solution.fitness.values is not None, \
        "complete_solution must have a real value."

    if complete_solution.fitness.values[0] > 0:
        return True
    else:
        return False