code: def get_key(self):
          
          if not isinstance(self.key, Unparseable):
              return self.key
  
          line = self.source[self.col_offset:]
          regex = re.compile('''pyconfig\.[eginst]+\(([^,]+).*?\)''')
          match = regex.match(line)
          if not match:
              return Unparseable()
  
          return "<%s>" % match.group(1)
docs: Return the call key, even if it has to be parsed from the source.