old_contents: from pathlib import Path
  
  from django import template
  from django.template.defaultfilters import stringfilter
  
  register = template.Library()
  
  
  @register.filter
  @stringfilter
  def filename(path):
      """Removes traceback lines from a string (if any). It has no effect when
      no 'Traceback' pattern has been found.
  
      Returns: raws before the 'Traceback' pattern
      """
      return Path(path).name
  
new_contents: from pathlib import Path
  
  from django import template
  from django.template.defaultfilters import stringfilter
  
  register = template.Library()
  
  
  @register.filter
  @stringfilter
  def filename(path):
      """Removes parent path from a relative or absolute filename
  
      Returns: the filename
      """
      return Path(path).name
  
subject: Fix filename template tag docstring