Write a function curve$($grades$)$ that takes a list of student grades from $0$ to $100,$ and assigns letter grades based on the following scheme: Find the best grade in the original list of grades For each grade in grades Assign A if grade is $>=$ best $-10$ Assign B if grade is $>=$ best $-20$ Assign C if grade is $>=$ best $-30$ Assign D if grade is $>=$ best $-40$ Assign F otherwise. Return a list of letter grades that corresponds to the initial list of grades. $($In case this makes you nervous, don$$t worry, we would never assign grades in this way!$)$