Build out a model to calculate the duration of a $5$ year bond with annual payments. Allow the user to input the coupon and yield. Model should calculate a bond price and a duration.

Use this model to calculate a duration for a $5\%$ coupon and $5\%$ yield. Now recalculate duration at $4\%.$ Calculate convexity $($choose some scenario and show me the convexity calculation$).$ Show all work.