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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def check(self, feature):
 """ Loop through all our feature flag checkers and return true if any of them are true. The order of handlers matters - we will immediately return True if any handler returns true. If you want to a handler to return False and stop the chain, raise the StopCheckingFeatureFlags exception."""

    found = False
    for handler in self.handlers:
      try:
        if handler(feature):
           return True
      except StopCheckingFeatureFlags:
        return False
      except NoFeatureFlagFound:
        pass
      else:
        found = True

    if not found:
      message = u"No feature flag defined for {feature}".format(feature=feature)
      if current_app.debug and current_app.config.get(RAISE_ERROR_ON_MISSING_FEATURES, False):
        raise KeyError(message)
      else:
        log.info(message)
        missing_feature.send(self, feature=feature)

    return False