The phrase "a thousand splendid suns," from the poem by saib-e-tabrizi, is quoted twice in the novel – once as laila’s family prepares to leave kabul, and again when she decides to return there from pakistan. it is also echoed in one of the final lines: "miriam is in laila’s own heart, where she shines with the bursting radiance of a thousand suns." discuss the thematic significance of this phrase.