class_docstr: A test result class that can print formatted text results to a stream.
  
  Used by TextTestRunner.
code: def addError(self, test, err):
      super(TextTestResult, self).addError(test, err)
      if self.showAll:
          self._write_status(test, "ERROR")
      elif self.dots:
          self.stream.write("E")
          self.stream.flush()
  
imports: import sys
  import time
  import warnings
  from .None import result
  from .case import _SubTest
  from .signals import registerResult
label_desc: Use image node_id 7 for calling the TextTestResult obj's underlying member method code with example usage: obj.addError(test, err) without return types