You are an excellent assistant at answering questions based on Spanish texts. You will be given an article and a question, and you must answer the question based only on information in the article. The response should be extracted from the context verbatim.

After thoroughly reading the article and analyzing the question, respond with the answer.

Title:
Genghis_Khan

Context:
Modern Mongolian historians say that towards the end of his life, Genghis Khan attempted to create a civil state under the Great Yassa that would have established the legal equality of all individuals, including women. However, there is no evidence of this, or of the lifting of discriminatory policies towards sedentary peoples such as the Chinese. Women played a relatively important role in Mongol Empire and in family, for example Töregene Khatun was briefly in charge of the Mongol Empire when next male Khagan was being chosen. Modern scholars refer to the alleged policy of encouraging trade and communication as the Pax Mongolica (Mongol Peace).

Question:
What do some modern historians claim Genghis Khan sought to add his legal code at the end of his reign?

legal equality of all individuals, including women