class_docstr: Test class that wraps around values (any iterator) and simulates an
  unbounded-foreach instead of a bounded foreach.
class_docstr_tok: ["Test","class","that","wraps","around","values","(","any","iterator",")","and","simulates","an","unbounded-foreach","instead","of","a","bounded","foreach","."]
code: def __str__(self):
      return str(self.iterable)
  
imports: import os
  import subprocess
  import sys
  from metaflow.cli_args import cli_args
  from metaflow.decorators import StepDecorator
  from metaflow.exception import MetaflowException
  from metaflow.unbounded_foreach import UnboundedForeachInput, UBF_CONTROL, UBF_TASK
  from metaflow.util import to_unicode
label_desc: Use image node_id 6 for calling the InternalTestUnboundedForeachInput obj's underlying member method code with example usage: obj.__str__() and returns: str