def insert_sort(data):
    """Sort a list of unique numbers in ascending order using insert sort. O(n^2).
    
    The process includes iterating through a list and ordering elements as they're visited.
    
    Args:
        data: data to sort (list of int)
    Returns:
        sorted list
    """
    
    sorted_data = data[:]
    
    # visit new elements
    for i, value in enumerate(sorted_data):
        # compare each new element with previously visited elements
        for j in range(i, -1, -1):
            # swap if needed
            if sorted_data[j] > value:
                sorted_data[j + 1] = sorted_data[j]
                sorted_data[j] = value
    
    return sorted_data