diff --git a/apkverity/src/util.rs b/apkverity/src/util.rs
index 415e99b..d2bc799 100644
--- a/apkverity/src/util.rs
+++ b/apkverity/src/util.rs
@@ -16,7 +16,6 @@
 
 use anyhow::{bail, Result};
 use nix::sys::stat::FileStat;
-use std::fs;
 use std::fs::File;
 use std::os::unix::fs::FileTypeExt;
 use std::os::unix::io::AsRawFd;
@@ -40,7 +39,7 @@
 
 /// Returns hexadecimal reprentation of a given byte array.
 pub fn hexstring_from(s: &[u8]) -> String {
-    s.iter().map(|byte| format!("{:02x}", byte)).reduce(|i, j| i + &j).unwrap_or(String::new())
+    s.iter().map(|byte| format!("{:02x}", byte)).reduce(|i, j| i + &j).unwrap_or_default()
 }
 
 /// fstat that accepts a path rather than FD