code: def __init__(self, deconame):
      from .plugins import STEP_DECORATORS
  
      decos = ", ".join(
          t.name
          for t in STEP_DECORATORS
          if not t.name.endswith("_internal")
      )
      msg = (
          "Unknown step decorator *{deconame}*. The following decorators are "
          "supported: *{decos}*".format(deconame=deconame, decos=decos)
      )
      super(UnknownStepDecoratorException, self).__init__(msg)
  
imports: from functools import partial
  import json
  import re
  import os
  import sys
  from .flowspec import FlowSpec
  from .exception import MetaflowInternalError, MetaflowException, InvalidDecoratorAttribute
  from metaflow._vendor import click
label_desc: Use image node_id 1 to create a new UnknownStepDecoratorException object from inherited base classes: MetaflowException with example: obj = UnknownStepDecoratorException(deconame)