diff --git a/src/crypto/cipher_key.rs b/src/crypto/cipher_key.rs
index a0555b1..f4cc387 100644
--- a/src/crypto/cipher_key.rs
+++ b/src/crypto/cipher_key.rs
@@ -1,7 +1,7 @@
 use crate::crypto::cipher::{aes, tdes, tdes_2k, tdes_3k, Cipher};
 use crate::crypto::cipher_type::CipherType;
 use crate::crypto::cipher_type::CipherType::*;
-use crate::error::Error;
+
 use crate::error::Result;
 
 use simple_error::simple_error;
diff --git a/src/desfire/desfire.rs b/src/desfire/desfire.rs
index f06e5ea..2e56181 100644
--- a/src/desfire/desfire.rs
+++ b/src/desfire/desfire.rs
@@ -15,8 +15,8 @@ use crate::error::{Error, Result};
 use crate::iso7816_4::apducommand::{APDUCommand, IsoCase};
 use crate::{error, Card};
 use num_traits::FromPrimitive;
-use std::fs::read;
-use std::usize::MAX;
+
+
 
 pub const MAX_BYTES_PER_TRANSACTION: usize = 47;
 
@@ -780,23 +780,23 @@ mod tests {
         generate_file_access_rights, generate_keysetting1, generate_keysetting2,
         generate_session_key_aes, generate_session_key_des, Desfire,
     };
-    use crate::desfire::CryptoOperationsType::TDES;
+    
     use crate::desfire::{
         ChangeApplicationKey, ChangeMasterKey, ChangeMasterKeySettings, CreateDeleteFile,
         CryptoOperationsType, FileAccessRights, FileCommunication, FileDirectoryAccess,
         FileIdentifiers,
     };
-    use crate::error::Error::{CardError, InvalidKeyID};
+    use crate::error::Error::{CardError};
     use crate::error::Result;
-    use crate::iso7816_4::apdustatuswords::APDUStatusWord::OK;
+    
     use crate::{APDUCommand, APDUResponse, Card as CardTrait};
     use hex_literal::hex;
-    use mockall::{mock, predicate};
-    use pcsc::{Card, Context, Disposition, Error, Protocols, Scope, ShareMode, MAX_BUFFER_SIZE};
+    use mockall::{mock};
+    use pcsc::{Card, Context, Protocols, Scope, ShareMode, MAX_BUFFER_SIZE};
     use std::convert::TryFrom;
-    use std::ffi::{CStr, CString};
-    use std::fs::{read, File};
-    use std::ops::Deref;
+    use std::ffi::{CString};
+    
+    
 
     mock! {
         pub VirtualCard {}
@@ -820,7 +820,7 @@ mod tests {
                 .connect(&self.reader, ShareMode::Shared, Protocols::ANY)
             {
                 Ok(card) => Some(card),
-                Err(err) => {
+                Err(_err) => {
                     // eprintln!("Failed to connect to card: {}", err);
                     return Err(CardError);
                 }
@@ -845,7 +845,7 @@ mod tests {
                 .transmit(apdu.as_slice(), &mut rapdu_buf)
             {
                 Ok(rapdu) => rapdu,
-                Err(err) => {
+                Err(_err) => {
                     // eprintln!("Failed to transmit APDU command to card: {}", err);
                     return Err(CardError);
                 }
@@ -986,7 +986,7 @@ mod tests {
     fn select_application_invalidaid() {
         let mock = MockVirtualCard::new();
 
-        let mut desfire = Desfire {
+        let desfire = Desfire {
             card: Some(Box::new(mock)),
             cbc_iv: None,
             session_key: None,
@@ -1001,7 +1001,7 @@ mod tests {
         // Establish a PC/SC context.
         let ctx = match Context::establish(Scope::User) {
             Ok(ctx) => ctx,
-            Err(err) => {
+            Err(_err) => {
                 // eprintln!("Failed to establish context: {}", err);
                 std::process::exit(1);
             }
@@ -1011,7 +1011,7 @@ mod tests {
         let mut readers_buf = [0; 2048];
         let mut readers = match ctx.list_readers(&mut readers_buf) {
             Ok(readers) => readers,
-            Err(err) => {
+            Err(_err) => {
                 // eprintln!("Failed to list readers: {}", err);
                 std::process::exit(1);
             }
@@ -1073,7 +1073,7 @@ mod tests {
             });
 
         let rndA = hex!("5f7d1dd12d979173");
-        let mut key = CipherKey::new_empty(CipherType::TDES).unwrap();
+        let key = CipherKey::new_empty(CipherType::TDES).unwrap();
         // println!("{:x?}", key.key.deref());
 
         let mut desfire = Desfire {
@@ -1115,7 +1115,7 @@ mod tests {
         // Establish a PC/SC context.
         let ctx = match Context::establish(Scope::User) {
             Ok(ctx) => ctx,
-            Err(err) => {
+            Err(_err) => {
                 // eprintln!("Failed to establish context: {}", err);
                 std::process::exit(1);
             }
@@ -1125,7 +1125,7 @@ mod tests {
         let mut readers_buf = [0; 2048];
         let mut readers = match ctx.list_readers(&mut readers_buf) {
             Ok(readers) => readers,
-            Err(err) => {
+            Err(_err) => {
                 // eprintln!("Failed to list readers: {}", err);
                 std::process::exit(1);
             }
@@ -1156,10 +1156,10 @@ mod tests {
 
         desfire.select_application(0x000000);
 
-        let mut key = CipherKey::new_empty(CipherType::TDES).unwrap();
+        let key = CipherKey::new_empty(CipherType::TDES).unwrap();
         match desfire.authenticate_iso_des(0x00, key.key.as_ref(), None) {
             Ok(_) => {}
-            Err(err) => {
+            Err(_err) => {
                 // eprintln!("Failed to authenticate: {}", err);
                 panic!("Failed to authenticate");
             }
@@ -1188,7 +1188,7 @@ mod tests {
         }));
 
         let rndA = hex!("2176770e7a6eb4bef00d5e4b201d1e57");
-        let mut key = CipherKey::new_empty(CipherType::AES).unwrap();
+        let key = CipherKey::new_empty(CipherType::AES).unwrap();
         // println!("{:x?}", key.key.deref());
 
         let mut desfire = Desfire {
@@ -1239,7 +1239,7 @@ mod tests {
                 })
             });
 
-        let mut desfire = Desfire {
+        let desfire = Desfire {
             card: Some(Box::new(mock)),
             cbc_iv: None,
             session_key: None,
@@ -1263,7 +1263,7 @@ mod tests {
                 })
             });
 
-        let mut desfire = Desfire {
+        let desfire = Desfire {
             card: Some(Box::new(mock)),
             cbc_iv: None,
             session_key: None,
@@ -1275,9 +1275,9 @@ mod tests {
     #[test]
     #[should_panic(expected = "InvalidApplicationID")]
     fn create_application_invalid_aid() {
-        let mut mock = MockVirtualCard::new();
+        let mock = MockVirtualCard::new();
 
-        let mut desfire = Desfire {
+        let desfire = Desfire {
             card: Some(Box::new(mock)),
             cbc_iv: None,
             session_key: None,
@@ -1309,7 +1309,7 @@ mod tests {
     #[test]
     #[should_panic(expected = "InvalidKeyID")]
     fn change_key_aes_invalid_keyno() {
-        let mut mock = MockVirtualCard::new();
+        let mock = MockVirtualCard::new();
 
         let mut desfire = Desfire {
             card: Some(Box::new(mock)),
@@ -1346,7 +1346,7 @@ mod tests {
     #[test]
     #[should_panic(expected = "InvalidKeyID")]
     fn change_other_key_aes_invalid_keyno() {
-        let mut mock = MockVirtualCard::new();
+        let mock = MockVirtualCard::new();
 
         let mut desfire = Desfire {
             card: Some(Box::new(mock)),
@@ -1374,7 +1374,7 @@ mod tests {
                 })
             });
 
-        let mut desfire = Desfire {
+        let desfire = Desfire {
             card: Some(Box::new(mock)),
             cbc_iv: None,
             session_key: None,
@@ -1390,9 +1390,9 @@ mod tests {
     #[test]
     #[should_panic(expected = "InvalidFileID")]
     fn create_file_standard_invalid_file_id() {
-        let mut mock = MockVirtualCard::new();
+        let mock = MockVirtualCard::new();
 
-        let mut desfire = Desfire {
+        let desfire = Desfire {
             card: Some(Box::new(mock)),
             cbc_iv: None,
             session_key: None,
@@ -1421,7 +1421,7 @@ mod tests {
                 })
             });
 
-        let mut desfire = Desfire {
+        let desfire = Desfire {
             card: Some(Box::new(mock)),
             cbc_iv: None,
             session_key: None,
@@ -1459,7 +1459,7 @@ mod tests {
                 })
             });
 
-        let mut desfire = Desfire {
+        let desfire = Desfire {
             card: Some(Box::new(mock)),
             cbc_iv: None,
             session_key: None,
@@ -1472,9 +1472,9 @@ mod tests {
     #[test]
     #[should_panic(expected = "InvalidFileID")]
     fn write_data_invalid_file_id() {
-        let mut mock = MockVirtualCard::new();
+        let mock = MockVirtualCard::new();
 
-        let mut desfire = Desfire {
+        let desfire = Desfire {
             card: Some(Box::new(mock)),
             cbc_iv: None,
             session_key: None,
@@ -1503,7 +1503,7 @@ mod tests {
                 })
             });
 
-        let mut desfire = Desfire {
+        let desfire = Desfire {
             card: Some(Box::new(mock)),
             cbc_iv: None,
             session_key: None,
@@ -1525,7 +1525,7 @@ mod tests {
             body: Some(hex!("5465737431323334000000000000000000000000000000000000000000000000809a9bedbc559a5b9100").to_vec())
         }));
 
-        let mut desfire = Desfire {
+        let desfire = Desfire {
             card: Some(Box::new(mock)),
             cbc_iv: None,
             session_key: None,
@@ -1565,7 +1565,7 @@ mod tests {
                 })
             });
 
-        let mut desfire = Desfire {
+        let desfire = Desfire {
             card: Some(Box::new(mock)),
             cbc_iv: None,
             session_key: None,
@@ -1581,9 +1581,9 @@ mod tests {
     #[test]
     #[should_panic(expected = "InvalidFileID")]
     fn read_data_invalid_file_id() {
-        let mut mock = MockVirtualCard::new();
+        let mock = MockVirtualCard::new();
 
-        let mut desfire = Desfire {
+        let desfire = Desfire {
             card: Some(Box::new(mock)),
             cbc_iv: None,
             session_key: None,