Exercise $4$: Calculator Part $3$ In python

In this exercise, you'll be using the functions you made from

exercises $3$ and $4$ to program a four$-$function calculator. This

calculator should have the following features:

add$($num$1,$ num$2),$ sub$($num$1,$ num$2),$ multiply$($num$1,$

num$2),$ and divide$($num$1,$ num$2),$ where num $1$ and num $2$

may be given as floats or ints

the ability to continue performing user calculations until the

user types "exit".

user can select which operation they would like to perform

$($either "add", "subtract", "multiply", "divide"$)$

user can indicate whether they would like to use the

previous value as the first number in the next calculation

$("$yes$"$ or $"$no$").$ If the user says "yes", the result of the

previous calculation should become num $1$ for the next

calculation.

displays all calculations to $2$ decimal places.

Note: NEVER round the calculations. Display the result

rounded to two decimal places, but always save the exact,

un$-$rounded value.