What is the poem that expresses the poet's homesickness in Du Fu's Spring Hope?

"After three months of war, a letter from home is worth a ton of gold." The poet thought: The war has been going on for a spring and it is still not over. Emperor Xuanzong of the Tang Dynasty was forced to flee to Shu, and Tang Suzong just succeeded to the throne. However, loyalists have not yet achieved a favorable situation and failed to recover Xijing. It seems that the war will last for a long time. I still remember that I was captured and locked up in the enemy camp. I haven't heard from my wife and children for a long time. Their lives are uncertain, and I don't know what happened. If only I could get a letter from home. "A letter from home is worth a ton of gold" contains a lot of bitterness and expectation, which reflects the poet's urgent mood in the case of news isolation and long-awaited situation. War is the real reason why a letter from home is better than "10,000 yuan", and it is also the empathy of all the people in war-stricken countries. It reflects the good wishes of the broad masses of people to oppose war and look forward to peace and stability, which naturally makes people cry.