docs: def new_reservoir(reservoir_type='uniform', *reservoir_args, **reservoir_kwargs):
      """
      Build a new reservoir
      """
  
      try:
          reservoir_cls = RESERVOIR_TYPES[reservoir_type]
      except KeyError:
          raise InvalidMetricError("Unknown reservoir type: {}".format(reservoir_type))
  
      return reservoir_cls(*reservoir_args, **reservoir_kwargs)