<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def write(self, value):
 """ Appends bytes flat to the deque. So iterables will be unpacked. """

        if hasattr(value, '__iter__'):
            bytearray(value)
            self.extend(value)
        else:
            bytearray([value])
            self.append(value)