class_docstr: Utility function to set output either at the global level or on a
  specific object.
  
  To set output globally use:
  
  output(options)
  
  Where options may be an options specification string (as accepted by
  the IPython opts magic) or an options specifications dictionary.
  
  For instance:
  
  output("backend='bokeh'") # Or equivalently
  output(backend='bokeh')
  
  To set save output from a specific object do disk using the
  'filename' argument, you can supply the object as the first
  positional argument and supply the filename keyword:
  
  curve = hv.Curve([1,2,3])
  output(curve, filename='curve.png')
  
  For compatibility with the output magic, you can supply the object
  as the second argument after the string specification:
  
  curve = hv.Curve([1,2,3])
  output("filename='curve.png'", curve)
  
  These two modes are equivalent to the IPython output line magic and
  the cell magic respectively.
code: def __init__(self, *args, **kwargs):
      # To not overwrite param.ParameterizedFunction signature below
      super().__init__(*args, **kwargs)
  
imports: import inspect
  import os
  import shutil
  import sys
  from collections import defaultdict
  from inspect import Parameter, Signature
  from pathlib import Path
  from types import FunctionType
  import param
  from pyviz_comms import extension
  from ..core import Dataset, Dimensioned, DynamicMap, HoloMap, Store, StoreOptions, ViewableElement, util
  from ..core.operation import Operation, OperationCallable
  from ..core.options import Keywords, Options, options_policy
  from ..core.overlay import Overlay
  from ..core.util import merge_options_to_dict
  from ..operation.element import function
  from ..streams import Params, Stream, streams_list_from_dict
  from .settings import OutputSettings, list_backends, list_formats
label_desc: Use image node_id 1 to create a new output object from inherited base classes: param with example: obj = output()