code: def add_headers(self, header_name, value, *values):
  		
  		if self.__ro_flag:
  			raise RuntimeError('ro')
  		header_name = self.normalize_name(header_name)
  		if header_name not in self.__headers.keys():
  			self.__headers[header_name] = [value]
  		else:
  			self.__headers[header_name].append(value)
  
  		for single_value in values:
  			self.__headers[header_name].append(single_value)
docs: Add new header
  
  		:param header_name: name of the header to add
  		:param value: header value
  		:param values: additional header values (in a result request/response must be concatenated by the coma \
  		or by the separate header string)
  		:return: None