code: def _to_string(self):
          
          parts = []
          if self.library:  # pylint: disable=no-member
              parts.extend([self.org, self.library])  # pylint: disable=no-member
              if self.branch:  # pylint: disable=no-member
                  parts.append(u"{prefix}@{branch}".format(prefix=self.BRANCH_PREFIX, branch=self.branch))  # pylint: disable=no-member
          if self.version_guid:  # pylint: disable=no-member
              parts.append(u"{prefix}@{guid}".format(prefix=self.VERSION_PREFIX, guid=self.version_guid))  # pylint: disable=no-member
          return u"+".join(parts)
docs: Return a string representing this location.