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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 AppConfigFlagHandler(feature=None):
 """ This is the default handler. It checks for feature flags in the current app's configuration. For example, to have 'unfinished_feature' hidden in production but active in development: config.py class ProductionConfig(Config):
 FEATURE_FLAGS = { 'unfinished_feature' : False, } class DevelopmentConfig(Config):
 FEATURE_FLAGS = { 'unfinished_feature' : True, } """

  if not current_app:
    log.warn(u"Got a request to check for {feature} but we're outside the request context. Returning False".format(feature=feature))
    return False

  try:
    return current_app.config[FEATURE_FLAGS_CONFIG][feature]
  except (AttributeError, KeyError):
    raise NoFeatureFlagFound()