text: def to_gro(item, output_filepath=None, trajectory_item=None, atom_indices='all',
             frame_indices='all'):
  
      raise NotImplementedError
  
  def from_gro(item, atom_indices='all', frame_indices='all'):
  
      from molsysmt.forms.files.api_gro import to_parmed_Structure as gro_to_parmed_Structure
      from molsysmt.native.io.topology.classes import from_parmed_Structure as parmed_Structure_to_molsysmt_Topology
  
      tmp_item = gro_to_parmed_Structure(item)
      tmp_item = parmed_Structure_to_molsysmt_Topology(tmp_item)
  
      return tmp_item
  
  