code: def get_used_entities(self,use_specs):
          
          if len(use_specs.strip()) == 0:
              return (self.pub_procs, self.pub_absints, self.pub_types, self.pub_vars)
          only = bool(self.ONLY_RE.match(use_specs))
          use_specs = self.ONLY_RE.sub('',use_specs)
          ulist = self.SPLIT_RE.split(use_specs)
          ulist[-1] = ulist[-1].strip()
          uspecs = {}
          for item in ulist:
              match = self.RENAME_RE.search(item)
              if match:
                  uspecs[match.group(1).lower()] = match.group(2)
              else:
                  uspecs[item.lower()] = item
          ret_procs = {}
          ret_absints = {}
          ret_types = {}
          ret_vars = {}
          for name, obj in self.pub_procs.items():
              name = name.lower()
              if only:
                  if name in uspecs:
                      ret_procs[name] = obj
              else:
                  ret_procs[name] = obj
          for name, obj in self.pub_absints.items():
              name = name.lower()
              if only:
                  if name in uspecs:
                      ret_absints[name] = obj
              else:
                  ret_absints[name] = obj
          for name, obj in self.pub_types.items():
              name = name.lower()
              if only:
                  if name in uspecs:
                      ret_types[name] = obj
              else:
                  ret_types[name] = obj
          for name, obj in self.pub_vars.items():
              name = name.lower()
              if only:
                  if name in uspecs:
                      ret_vars[name] = obj
              else:
                  ret_vars[name] = obj
          return (ret_procs,ret_absints,ret_types,ret_vars)
docs: Returns the entities which are imported by a use statement. These
          are contained in dicts.