THE DEVOUT SEVEN DAYS
Pope Pius XI wrote an Apostolic Brief recommending this practice, of praying to the Holy Virgin as Mary Immaculately conceived in the manner of St. Bonaventure, for obtaining the grace of a happy death. Although any seven successive days make be taken for this devotion, traditionally it is prayed the week preceding the Feast of the Immaculate Conception, December 8, or during the Octave of the Feast of St. Joseph, March 19. St. Bonaventure was devoted to the Immaculata and is considered a mystic as well as called the Seraphic Saint.
We do not possess a copy of St. Bonaventure's Marian prayers, but in his Brief, the Pontiff stated that any prayer in honor of the Immaculate Conception with the intention of requesting the grace of a holy death from Our Lady would be equivalent, so here is the one CT has:
PRAYERO Virgin Immaculate, who wast pleasing in the Lord's sight and didst become His Mother, look graciously upon the wretched who implore thy mighty patronage. The wicked serpent, against whom the primal curse was hurled, continues none the less to wage war and to lay snares for the unhappy child of Eve. Ah, do thou, our Blessed mother, our Queen and Advocate, who from the first instant of thy conception didst crush the head of our enemy, receive the prayers that we unite single-heartedly to thine and conjure thee to offer at the throne of God, that we may never fall into the snares that are laid for us, in such wise that we may all come to the haven of salvation, within the armor of the grace of final perseverance; and in the midst of so many dangers may holy Church and her militant soldiers everywhere sing once more the hymn of deliverance, victory, and peace. Amen.