docs: def has(self, decorated_function, *args, **kwargs):
  		""" Check if there is a result for given function
  
  		:param decorated_function: called function (original)
  		:param args: args with which function is called
  		:param kwargs: kwargs with which function is called
  
  		:return: None
  		"""
  		return self.get_cache(decorated_function, *args, **kwargs).has_value