code: def render_pep440_bare(pieces):
      
      if pieces["closest-tag"]:
          rendered = pieces["closest-tag"]
          if pieces["distance"] or pieces["dirty"]:
              rendered += ".%d" % pieces["distance"]
              if pieces["dirty"]:
                  rendered += ".dev0"
      else:
          # exception #1
          rendered = "0.%d" % pieces["distance"]
          if pieces["dirty"]:
              rendered += ".dev0"
      return rendered
docs: TAG[.DISTANCE[.dev0]] .
  
      The ".dev0" means dirty.
  
      Eexceptions:
      1: no tags. 0.DISTANCE[.dev0]