from collections import deque
from threading import Thread, Lock

class MyDeque:
    def __init__(self,maxlen=1):
        self.len = maxlen
        self.dq = deque(maxlen=maxlen)
        self.lock = Lock()

    def __del__(self):
        del self.dq

    def isfull(self):
        if len(self.dq) == self.len:
            return True
        return False

    def myappend(self,object):
        with self.lock:
            self.dq.append(object)

    def mypopleft(self):
        object = None
        with self.lock:
            if self.dq:
                object = self.dq.popleft()
            else:
                pass
        return object

    def myclear(self):
        with self.lock:
            self.dq.clear()