class_docstr: Variant of Queue that retrieves open entries in priority order (lowest first).
  
  Entries are typically tuples of the form:  (priority number, data).
code: def _init(self, maxsize):
      self.queue = []
  
imports: import threading
  import types
  from collections import deque
  from heapq import heappush, heappop
  from time import monotonic
label_desc: Use image node_id 1 for calling the PriorityQueue obj's underlying member method code with example usage: obj._init(maxsize) without return types