Use the function design recipe to develop a function named repeat$\_$pattern. The function

header $($with missing type annotations$)$ is: repeat$\_$pattern$($element$1,$ element$2,$ n$).$

Parameters element$1$ and element$2$ are strings containing at least one character. Parameter n

is a positive integer.

The function returns a long string consisting of n occurrences of the pattern element$1,$

separated by the string element$2$