text: import six
  import sys
  import time
  import traceback
  import random
  import asyncio
  import functools
  
  
  # Borrowed from https://github.com/rholder/retrying
  
  MAX_WAIT = 1073741823
  
  def _retry_if_exception_of_type(retryable_types):
      def _retry_if_exception_these_types(exception):
          return isinstance(exception, retryable_types)
      return _retry_if_exception_these_types
  
  def retryable(*dargs, **dkw):
      """
      Decorator function that instantiates the Retrying object
      @param *dargs: positional arguments passed to Retrying object
      @param **dkw: keyword arguments passed to the Retrying object
      """
      # support both @retry and @retry() as valid syntax
      if len(dargs) == 1 and callable(dargs[0]):
          def wrap_simple(f):
              @six.wraps(f)
              def wrapped_f(*args, **kw):
                  return Retrying().call(f, *args, **kw)
              return wrapped_f
          return wrap_simple(dargs[0])
  
      else:
          def wrap(f):
              @six.wraps(f)
              def wrapped_f(*args, **kw):
                  return Retrying(*dargs, **dkw).call(f, *args, **kw)
              return wrapped_f
          return wrap
  
  
  def async_retryable(*dargs, **dkw):
      if len(dargs) == 1 and callable(dargs[0]):
          def wrap_simple(f):
              @six.wraps(f)
              async def aio_wrapped_f(*args, loop=None, executor=None, **kw):
                  if loop is None:
                      loop = asyncio.get_event_loop()
                  pfunc = functools.partial(Retrying().call, *args, **kw)
                  return await loop.run_in_executor(executor, pfunc)
              return aio_wrapped_f
          return wrap_simple(dargs[0])
  
      else:
          def wrap(f):
              @six.wraps(f)
              async def aio_wrapped_f(*args, loop=None, executor=None, **kw):
                  if loop is None:
                      loop = asyncio.get_event_loop()
                  pfunc = functools.partial(Retrying(*dargs, **dkw).call, *args, **kw)
                  return await loop.run_in_executor(executor, pfunc)
              return aio_wrapped_f
          return wrap
  
  
  class Retrying(object):
      def __init__(self,
                   stop=None, wait=None,
                   stop_max_attempt_number=None,
                   stop_max_delay=None,
                   wait_fixed=None,
                   wait_random_min=None, wait_random_max=None,
                   wait_incrementing_start=None, wait_incrementing_increment=None,
                   wait_incrementing_max=None,
                   wait_exponential_multiplier=None, wait_exponential_max=None,
                   retry_on_exception=None,
                   retry_on_result=None,
                   wrap_exception=False,
                   stop_func=None,
                   wait_func=None,
                   wait_jitter_max=None,
                   before_attempts=None,
                   after_attempts=None):
  
          self._stop_max_attempt_number = 5 if stop_max_attempt_number is None else stop_max_attempt_number
          self._stop_max_delay = 100 if stop_max_delay is None else stop_max_delay
          self._wait_fixed = 1000 if wait_fixed is None else wait_fixed
          self._wait_random_min = 0 if wait_random_min is None else wait_random_min
          self._wait_random_max = 1000 if wait_random_max is None else wait_random_max
          self._wait_incrementing_start = 0 if wait_incrementing_start is None else wait_incrementing_start
          self._wait_incrementing_increment = 100 if wait_incrementing_increment is None else wait_incrementing_increment
          self._wait_exponential_multiplier = 1 if wait_exponential_multiplier is None else wait_exponential_multiplier
          self._wait_exponential_max = MAX_WAIT if wait_exponential_max is None else wait_exponential_max
          self._wait_incrementing_max = MAX_WAIT if wait_incrementing_max is None else wait_incrementing_max
          self._wait_jitter_max = 0 if wait_jitter_max is None else wait_jitter_max
          self._before_attempts = before_attempts
          self._after_attempts = after_attempts
  
          # TODO add chaining of stop behaviors
          # stop behavior
          stop_funcs = []
          if stop_max_attempt_number is not None: stop_funcs.append(self.stop_after_attempt)
  
          if stop_max_delay is not None: stop_funcs.append(self.stop_after_delay)
  
          if stop_func is not None: self.stop = stop_func
          elif stop is None: self.stop = lambda attempts, delay: any(f(attempts, delay) for f in stop_funcs)
          else: self.stop = getattr(self, stop)
  
          # TODO add chaining of wait behaviors
          # wait behavior
          wait_funcs = [lambda *args, **kwargs: 0]
          if wait_fixed is not None: wait_funcs.append(self.fixed_sleep)
          if wait_random_min is not None or wait_random_max is not None: wait_funcs.append(self.random_sleep)
          if wait_incrementing_start is not None or wait_incrementing_increment is not None: wait_funcs.append(self.incrementing_sleep)
          if wait_exponential_multiplier is not None or wait_exponential_max is not None: wait_funcs.append(self.exponential_sleep)
          
          if wait_func is not None: self.wait = wait_func
  
          elif wait is None: self.wait = lambda attempts, delay: max(f(attempts, delay) for f in wait_funcs)
  
          else: self.wait = getattr(self, wait)
  
          # retry on exception filter
          if retry_on_exception is None: self._retry_on_exception = self.always_reject
          else:
              # this allows for providing a tuple of exception types that
              # should be allowed to retry on, and avoids having to create
              # a callback that does the same thing
              if isinstance(retry_on_exception, (tuple)): retry_on_exception = _retry_if_exception_of_type(retry_on_exception)
              self._retry_on_exception = retry_on_exception
  
          # retry on result filter
          if retry_on_result is None: self._retry_on_result = self.never_reject
          else: self._retry_on_result = retry_on_result
          self._wrap_exception = wrap_exception
  
      def stop_after_attempt(self, previous_attempt_number, delay_since_first_attempt_ms):
          """Stop after the previous attempt >= stop_max_attempt_number."""
          return previous_attempt_number >= self._stop_max_attempt_number
  
      def stop_after_delay(self, previous_attempt_number, delay_since_first_attempt_ms):
          """Stop after the time from the first attempt >= stop_max_delay."""
          return delay_since_first_attempt_ms >= self._stop_max_delay
  
      @staticmethod
      def no_sleep(previous_attempt_number, delay_since_first_attempt_ms):
          """Don't sleep at all before retrying."""
          return 0
  
      def fixed_sleep(self, previous_attempt_number, delay_since_first_attempt_ms):
          """Sleep a fixed amount of time between each retry."""
          return self._wait_fixed
  
      def random_sleep(self, previous_attempt_number, delay_since_first_attempt_ms):
          """Sleep a random amount of time between wait_random_min and wait_random_max"""
          return random.randint(self._wait_random_min, self._wait_random_max)
  
      def incrementing_sleep(self, previous_attempt_number, delay_since_first_attempt_ms):
          """
          Sleep an incremental amount of time after each attempt, starting at
          wait_incrementing_start and incrementing by wait_incrementing_increment
          """
          result = self._wait_incrementing_start + (self._wait_incrementing_increment * (previous_attempt_number - 1))
          result = min(result, self._wait_incrementing_max)
          result = max(result, 0)
          return result
  
      def exponential_sleep(self, previous_attempt_number, delay_since_first_attempt_ms):
          exp = 2 ** previous_attempt_number
          result = self._wait_exponential_multiplier * exp
          result = min(result, self._wait_exponential_max)
          result = max(result, 0)
          return result
  
      @staticmethod
      def never_reject(result): return False
  
      @staticmethod
      def always_reject(result): return True
  
      def should_reject(self, attempt):
          reject = False
          if attempt.has_exception: reject |= self._retry_on_exception(attempt.value[1])
          else: reject |= self._retry_on_result(attempt.value)
          return reject
  
      def call(self, fn, *args, **kwargs):
          start_time = int(round(time.time() * 1000))
          attempt_number = 1
          while True:
              if self._before_attempts: self._before_attempts(attempt_number)
              try: attempt = Attempt(fn(*args, **kwargs), attempt_number, False)
              except:
                  tb = sys.exc_info()
                  attempt = Attempt(tb, attempt_number, True)
  
              if not self.should_reject(attempt): return attempt.get(self._wrap_exception)
              if self._after_attempts: self._after_attempts(attempt_number)
  
              delay_since_first_attempt_ms = int(round(time.time() * 1000)) - start_time
              if self.stop(attempt_number, delay_since_first_attempt_ms):
                  if not self._wrap_exception and attempt.has_exception:
                      # get() on an attempt with an exception should cause it to be raised, but raise just in case
                      raise attempt.get()
                  else:
                      raise RetryError(attempt)
              else:
                  sleep = self.wait(attempt_number, delay_since_first_attempt_ms)
                  if self._wait_jitter_max:
                      jitter = random.random() * self._wait_jitter_max
                      sleep = sleep + max(0, jitter)
                  time.sleep(sleep / 1000.0)
  
              attempt_number += 1
  
  
  class Attempt(object):
      """
      An Attempt encapsulates a call to a target function that may end as a
      normal return value from the function or an Exception depending on what
      occurred during the execution.
      """
      def __init__(self, value, attempt_number, has_exception):
          self.value = value
          self.attempt_number = attempt_number
          self.has_exception = has_exception
  
      def get(self, wrap_exception=False):
          """
          Return the return value of this Attempt instance or raise an Exception.
          If wrap_exception is true, this Attempt is wrapped inside of a
          RetryError before being raised.
          """
          if not self.has_exception: return self.value
          if wrap_exception: raise RetryError(self)
          else: six.reraise(self.value[0], self.value[1], self.value[2])
  
      def __repr__(self):
          if self.has_exception: return "Attempts: {0}, Error:\n{1}".format(self.attempt_number, "".join(traceback.format_tb(self.value[2])))
          else: return "Attempts: {0}, Value: {1}".format(self.attempt_number, self.value)
  
  
  class RetryError(Exception):
      """
      A RetryError encapsulates the last Attempt instance right before giving up.
      """
      def __init__(self, last_attempt):
          self.last_attempt = last_attempt
  
      def __str__(self):
          return "RetryError[{0}]".format(self.last_attempt)