code: def s_get(self, quant):
          
          if quant < 2:
              # special case, just return that unsigned value
              # quant can also be 0
              return self.u_get(quant)
  
          sign = self.u_get(1)
          raw_number = self.u_get(quant - 1)
          if sign == 0:
              # positive, simplest case
              number = raw_number
          else:
              # negative, complemento a 2
              complement = 2 ** (quant - 1) - 1
              number = -1 * ((raw_number ^ complement) + 1)
          return number
docs: Return a number using the given quantity of signed bits.