code: def get_protein_refs(self, hms_lincs_id):
          
          # TODO: We could get phosphorylation states from the protein data.
          refs = {'HMS-LINCS': hms_lincs_id}
  
          entry = self._get_entry_by_id(self._prot_data, hms_lincs_id)
          # If there is no entry for this ID
          if not entry:
              return refs
          mappings = dict(egid='Gene ID', up='UniProt ID')
          for k, v in mappings.items():
              if entry.get(v):
                  refs[k.upper()] = entry.get(v)
          return refs
docs: Get the refs for a protein from the LINCs protein metadata.
  
          Parameters
          ----------
          hms_lincs_id : str
              The HMS LINCS ID for the protein
  
          Returns
          -------
          dict
              A dictionary of protein references.