class_docstr: A progress publisher that records a trace of model states for testing.
      
class_docstr_tok: ["A","progress","publisher","that","records","a","trace","of","model","states","for","testing","."]
code: def __init__(self):
      self.trace = []
  
imports: from collections import namedtuple
  import time
  from interface import implements
  from zipline.utils.compat import contextmanager, escape_html
  from zipline.utils.string_formatting import bulleted_list
  from .iface import PipelineHooks
label_desc: Use image node_id 1 to create a new TestingProgressPublisher object from inherited base classes: object with example: obj = TestingProgressPublisher()