def __init__(self, initial_map=None):
    if initial_map:
      self.counters = initial_map
    else:
      self.counters = {}
Set up session for main service object.
dataset/ETHPy150Open AppScale/appscale/AppServer/google/appengine/ext/mapreduce/model.py/CountersMap.__init__--crossover with--dataset/ETHPy150Open MediaMath/t1-python/terminalone/service.py/T1.__init__