Add a cell to create a dataframe containing grade for four students choose the name of the students and use the names as index. For columns create four columns to reflect the months April, May, June, July. Set grade items for each student for each month to be between $0$ and $100.$ Name the dataframe fristname$\_$grades. Carry out the following using pandas operations:

$1.$ Print out the average for the month of April

$2.$ Adjust all the grades by $2\%($i$.$e$.$ increase$)$

$3.$ Printout the grades for the month of may that are higher than $50\%$

$4.$ Group the failing students i$.$e$.$ the students with average over four month below $50\%$