Define a function string_bits(str1) that returns a new string made of every other (every two) charachter starting with the first.Examplestr1 = 'Hello'string_bits('Hello')Expected output:'Hlo'

Define a function front_times(str1, n) that returns n copies of the front. n is a non-negative int. The front of the string is the first 3 chars, or whatever is there if the string is less than length 3.Examplestr1 = 'Chocolate'front_times(str1, 2) → 'ChoCho'Expected output:'ChoCho'str2 = 'ab'front_times(str2, 2) → 'abab'Expected output:'abab'Hint:use string slicing to get substringuse str * num, you will get repeat copy of str.for example, 'hello' * 3 => 'hellohellohello'

Write a program to return a string from a given string s where all occurrences of the first char of the string except the first occurrence have been changed to '$'.Input Format:The number of test cases. For each testcase there will be a single line of input as explained following.The single line consists of a string.Output Format:Resultant stringSample Input:1"restart"Sample Output:"resta$t"

写一个函数slice_from(string: str, start: int, end: int) -> strstring它返回从索引start到（但不包括）索引的字符end。请注意，包含起始索引处的字符但排除结束索引处的字符这一特性是默认的切片行为。写一个函数reverse_string(string: str) -> strstring它以相反的顺序返回字符。slice_from要获得and任务的学分reverse_string，您必须仅使用单个切片语句。例子>>> slice_from("abcdefghi", 3, 7)'defg'>>> reverse_string("abcd")'dcba'

Given a string to the function string_expand() , do complete it. String is made up of a character followed by integer. Do create a new string in which each character occurs for the respective number of times given  and return the newly created string.Input Format:No need to read input , as it is predefined in main.Output Format:No need to print just return the string from function.Constraints:1 <= String <= 10^4Sample Input 1:t12k20a1c5Sample Output 1:ttttttttttttkkkkkkkkkkkkkkkkkkkkacccccSample Input 2:a2b1c3Sample Output 2:aabccc

You are given a positive integer n.A binary string x is valid if all substrings of x of length 2 contain at least one "1".Return all valid strings with length n, in any order. Example 1:Input: n = 3Output: ["010","011","101","110","111"]Explanation:The valid strings of length 3 are: "010", "011", "101", "110", and "111".Example 2:Input: n = 1Output: ["0","1"]Explanation:The valid strings of length 1 are: "0" and "1".