text: # Copyright 2017 Robert Csordas. All Rights Reserved.
  #
  # Licensed under the Apache License, Version 2.0 (the "License");
  # you may not use this file except in compliance with the License.
  # You may obtain a copy of the License at
  #
  # http://www.apache.org/licenses/LICENSE-2.0
  #
  # Unless required by applicable law or agreed to in writing, software
  # distributed under the License is distributed on an "AS IS" BASIS,
  # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  # See the License for the specific language governing permissions and
  # limitations under the License.
  #
  # ==============================================================================
  
  import time
  
  
  class OnceEvery:
      def __init__(self, interval):
          self._interval = interval
          self._last_check = 0
  
      def __call__(self):
          now = time.time()
          if now - self._last_check >= self._interval:
              self._last_check = now
              return True
          else:
              return False
  
  
  class Measure:
      def __init__(self, average=1):
          self._start = None
          self._average = average
          self._accu_value = 0.0
          self._history_list = []
  
      def start(self):
          self._start = time.time()
  
      def passed(self):
          if self._start is None:
              return None
  
          p = time.time() - self._start
          self._history_list.append(p)
          self._accu_value += p
          if len(self._history_list) > self._average:
              self._accu_value -= self._history_list.pop(0)
  
          return self._accu_value / len(self._history_list)
  