Implement a function that takes a string that consists of lowercase letters and digits and returns a string that consists of all digits and lowercase English letters that are not present in the string. The digits should come first, in ascending order, followed by characters, also in ascending order.Example$5="7985$interdisciplinary$12$"The returned string is $"0346$bfghjkmoquvwxz". It contains all missing digits in ascending order, followed by missing characters in ascending order.Function DescriptionComplete the function missingCharacters in the editor below.missing Characters has the following parameter$(5)$: string s: a stringReturnstring: a string as described aboveConstraints $0$ slength of $5100$ Each character s$[$i$]$ is in the range $[$a$-$z$]$ or $[0-9].$ The resulting string will be non$-$empty