code: def load_world(filename):
      
      import ecell4_base
  
      vinfo = ecell4_base.core.load_version_information(filename)
      if vinfo.startswith("ecell4-bd"):
          return ecell4_base.bd.World(filename)
      elif vinfo.startswith("ecell4-egfrd"):
          return ecell4_base.egfrd.World(filename)
      elif vinfo.startswith("ecell4-meso"):
          return ecell4_base.meso.World(filename)
      elif vinfo.startswith("ecell4-ode"):
          return ecell4_base.ode.World(filename)
      elif vinfo.startswith("ecell4-gillespie"):
          return ecell4_base.gillespie.World(filename)
      elif vinfo.startswith("ecell4-spatiocyte"):
          return ecell4_base.spatiocyte.World(filename)
      elif vinfo == "":
          raise RuntimeError("No version information was found in [{0}]".format(filename))
      raise RuntimeError("Unkown version information [{0}]".format(vinfo))
docs: Load a world from the given HDF5 filename.
      The return type is determined by ``ecell4_base.core.load_version_information``.
  
      Parameters
      ----------
      filename : str
          A HDF5 filename.
  
      Returns
      -------
      w : World
          Return one from ``BDWorld``, ``EGFRDWorld``, ``MesoscopicWorld``,
          ``ODEWorld``, ``GillespieWorld`` and ``SpatiocyteWorld``.