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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _execute(self, net):
 """Handle the combinational logic update rules for the given net. This function, along with edge_update, defined the semantics of the primitive ops. Function updates self.value accordingly. """

        if net.op in 'r@':
            return  # registers and memory write ports have no logic function
        elif net.op in self.simple_func:
            argvals = (self.value[arg] for arg in net.args)
            result = self.simple_func[net.op](*argvals)
        elif net.op == 'c':
            result = 0
            for arg in net.args:
                result = result << len(arg)
                result = result | self.value[arg]
        elif net.op == 's':
            result = 0
            source = self.value[net.args[0]]
            for b in net.op_param[::-1]:
                result = (result << 1) | (0x1 & (source >> b))
        elif net.op == 'm':
            # memories act async for reads
            memid = net.op_param[0]
            mem = net.op_param[1]
            read_addr = self.value[net.args[0]]
            if isinstance(mem, RomBlock):
                result = mem._get_read_data(read_addr)
            else:
                result = self.memvalue[memid].get(read_addr, self.default_value)
        else:
            raise PyrtlInternalError('error, unknown op type')

        self.value[net.dests[0]] = self._sanitize(result, net.dests[0])