code: def _el_orb(string):
      
      el_orbs = {}
      for split in string.split(','):
          orbs = split.split('.')
          orbs = [orbs[0], 's', 'p', 'd', 'f'] if len(orbs) == 1 else orbs
          el_orbs[orbs.pop(0)] = orbs
      return el_orbs
docs: Parse the element and orbital argument strings.
  
      The presence of an element without any orbitals means that we want to plot
      all of its orbitals.
  
      Args:
          string (str): The element and orbitals as a string, in the form
              ``"C.s.p,O"``.
  
      Returns:
          dict: The elements and orbitals as a :obj:`dict`. For example::
  
              {'Bi': ['s', 'px', 'py', 'd']}.
  
          If an element symbol is included with an empty list, then all orbitals
          for that species are considered.