code: def set_concluded_license(self, doc, lic):
          
          if self.has_package(doc) and self.has_file(doc):
              if not self.file_conc_lics_set:
                  self.file_conc_lics_set = True
                  if validations.validate_lics_conc(lic):
                      self.file(doc).conc_lics = lic
                      return True
                  else:
                      raise SPDXValueError('File::ConcludedLicense')
              else:
                  raise CardinalityError('File::ConcludedLicense')
          else:
              raise OrderError('File::ConcludedLicense')
docs: Raises OrderError if no package or file defined.
          Raises CardinalityError if already set.
          Raises SPDXValueError if malformed.