code: def _unbind(cls, boundname):
          
  
          try:
              fs = CPE2_3_FS(boundname)
          except:
              # CPE name is not formatted string
              try:
                  uri = CPE2_3_URI(boundname)
              except:
                  # CPE name is not URI but WFN
                  return CPE2_3_WFN(boundname)
              else:
                  return CPE2_3_WFN(uri.as_wfn())
          else:
              return CPE2_3_WFN(fs.as_wfn())
docs: Unbinds a bound form to a WFN.
  
          :param string boundname: CPE name
          :returns: WFN object associated with boundname.
          :rtype: CPE2_3_WFN