Start work on challenge 12.

src/bytes.rs

@@ -1,4 +1,5 @@
 #![allow(dead_code)]
+use rand::Rng;
 use std::fmt::Write; // need to import this trait
 
 #[derive(PartialEq, PartialOrd, Debug)]
@@ -15,6 +16,19 @@ impl Bytes {
         String::from(std::str::from_utf8(&v).unwrap())
     }
 
+    pub fn random(length: usize) -> Bytes {
+        Bytes(
+            (0..length)
+                .map(|_| rand::thread_rng().gen_range(0..255))
+                .collect(),
+        )
+    }
+
+    pub fn random_range(lower: usize, upper: usize) -> Bytes {
+        let length: usize = rand::thread_rng().gen_range(lower..upper);
+        Bytes::random(length)
+    }
+
     pub fn from_hex(s: &str) -> Bytes {
         if s.len() % 2 != 0 {
             panic!("Input string has uneven number of characters");