python

DNA? To match all the characters of a string (go over them one by one), we can use a for loop, for example with for letter in string: (letter and string being variables and can therefore have a different name) A DNA chain is represented by a sequence of letters "A, C, G, T" which represents a nucleic base. 1) Write a function which takes as input a character string and returns its length 2) Writing a function given a character string checks if it is a string DNA (therefore only with characters A, C, G, T) 3) Make a program which verifies that a chain is indeed DNA and if so displays the percentage of each base