code: def get_int(self, key: str) -> Optional[int]:
          
          v = self.get(key)
          if v is None:
              return None
          try:
              return int(v)
          except:
              raise ConfigTypeError(self.full_key(key), v, 'int')
docs: Returns an optional configuration value, as an int, by its key, or None if it doesn't exist.
          If the configuration value isn't a legal int, this function will throw an error.
  
          :param str key: The requested configuration key.
          :return: The configuration key's value, or None if one does not exist.
          :rtype: Optional[int]
          :raises ConfigTypeError: The configuration value existed but couldn't be coerced to int.