TwosComplement

def twos(twos):
    if len(twos)!=8:
        print("Invalid length")

    for i in twos:
            if int(i) > 1:
                print("invalid value")

    if twos[0]=="1":
        print("negative twos complement")
        twos = int(twos, 2)
        decimal = 256 - twos
        final_num = -decimal
        return(final_num)

    else:
        print("positive twos complement")
        number = int(twos,2)
        return(number)

print(twos("11110011"))

# Check with http://www.convertforfree.com/twos-complement-calculator/