code: def to_full_path(cls, path):
          
          if isinstance(path, SymbolicReference):
              path = path.path
          full_ref_path = path
          if not cls._common_path_default:
              return full_ref_path
          if not path.startswith(cls._common_path_default + "/"):
              full_ref_path = '%s/%s' % (cls._common_path_default, path)
          return full_ref_path
docs: :return: string with a full repository-relative path which can be used to initialize
              a Reference instance, for instance by using ``Reference.from_path``