My attempt to do it was like this, but at -997 I’m getting 998 instead of 996:

max_value = 1000

def calculate_parent_value(child_value):
    if abs(child_value) == max_value:
        return -child_value + 1
    elif abs(child_value) == max_value - 1:
        return -max_value if child_value > 0 else max_value - 2
    else:
        return -child_value + 1
        
calculate_parent_value(-997)

998
(and not 996). Is anyone able to fix the function ?