What is the purpose of the Chorus in Angelou's, The Complete Collected Poems of Maya Angelou?

The use of the Chorus gives some poems a songlike feeling. Often, choruses are used, such as "Pickin Em Up and Layin Em Down." Such repetition emphasizes the life of the characters in the repetitious work of a blue-collar laborer. The repetition may also emphasize the theme, as in "Still I Rise." The reputation of the title phrase stresses the theme of resilience on the part of the narrator.