def reverse_scl_map(x_elem):
    """Maps one element from x to the given class on SCL standart

    Parameters:
        x_elem (int): class value from the classification
    Returns:
        int: class number in the SCL format
   """
    if x_elem == 2:
        return 1
    if x_elem == 3:
        return 2
    if x_elem == 4:
        return 3
    return x_elem