class_docstr: Collector instances create children through collect()
  and thus iteratively build a tree.
docstr: represent a collection failure. 
docstr_tok: ["represent","a","collection","failure","."]
code: def repr_failure(self, excinfo):
      """represent a collection failure."""
      if excinfo.errisinstance(self.CollectError):
          exc = excinfo.value
          return str(exc.args[0])
  
      # Respect explicit tbstyle option, but default to "short"
      # (None._repr_failure_py defaults to "long" without "fulltrace" option).
      tbstyle = self.config.getoption("tbstyle", "auto")
      if tbstyle == "auto":
          tbstyle = "short"
  
      return self._repr_failure_py(excinfo, style=tbstyle)
  
imports: from __future__ import absolute_import
  from __future__ import division
  from __future__ import print_function
  import os
  import warnings
  import py
  import six
  import _pytest._code
  from _pytest.compat import getfslineno
  from _pytest.mark.structures import NodeKeywords
  from _pytest.outcomes import fail
label_desc: Use image node_id 2 for calling the Collector obj's underlying member method code with example usage: obj.repr_failure(excinfo) and returns: self, str