class_docstr: Singleton class wrapping to control the connections to Oanda.
  
  Params:
  
    - ``token`` (default:``None``): API access token
  
    - ``account`` (default: ``None``): account id
  
    - ``practice`` (default: ``False``): use the test environment
  
    - ``account_tmout`` (default: ``10.0``): refresh period for account
      value/cash refresh
class_docstr_tok: ["Singleton","class","wrapping","to","control","the","connections","to","Oanda",".","Params",":","-","``","token","``","(","default",":","``","None","``",")",":","API","access","token","-","``","account","``","(","default",":","``","None","``",")",":","account","id","-","``","practice","``","(","default",":","``","False","``",")",":","use","the","test","environment","-","``","account_tmout","``","(","default",":","``","10.0","``",")",":","refresh","period","for","account","value\/cash","refresh"]
code: def __init__(self):
      super(OandaStore, self).__init__()
  
      self.notifs = (
          collections.deque()
      )  # store notifications for cerebro
  
      self._env = None  # reference to cerebro for general notifications
      self.broker = None  # broker instance
      self.datas = list()  # datas that have registered over start
  
      self._orders = collections.OrderedDict()  # map order.ref to oid
      self._ordersrev = (
          collections.OrderedDict()
      )  # map oid to order.ref
      self._transpend = collections.defaultdict(collections.deque)
  
      self._oenv = (
          self._ENVPRACTICE if self.p.practice else self._ENVLIVE
      )
      self.oapi = API(
          environment=self._oenv,
          access_token=self.p.token,
          headers={"X-Accept-Datetime-Format": "UNIX"},
      )
  
      self._cash = 0.0
      self._value = 0.0
      self._evt_acct = threading.Event()
  
imports: from __future__ import absolute_import, division, print_function, unicode_literals
  import collections
  from datetime import datetime, timedelta
  import time
  import json
  import threading
  import oandapy
  import requests
  import backtrader
  from backtrader.metabase import MetaParams
  from backtrader.utils.py3 import queue, with_metaclass
  from backtrader.utils import AutoDict
label_desc: Use image node_id 3 to create a new OandaStore object from inherited base classes:  with example: obj = OandaStore()