diff --git a/androscalpel/src/apk.rs b/androscalpel/src/apk.rs
index 28f1769..bdfa0d5 100644
--- a/androscalpel/src/apk.rs
+++ b/androscalpel/src/apk.rs
@@ -2381,4 +2381,8 @@ impl Apk {
     pub fn from_json(json: &str) -> Result<Self> {
         Ok(serde_json::from_str(json)?)
     }
+
+    pub fn remove_class(&mut self, class: &IdType) {
+        self.classes.remove(class);
+    }
 }
diff --git a/androscalpel/src/lib.rs b/androscalpel/src/lib.rs
index 9c5d4b2..c9ad984 100644
--- a/androscalpel/src/lib.rs
+++ b/androscalpel/src/lib.rs
@@ -14,6 +14,7 @@ mod hashmap_vectorize;
 pub mod instructions;
 pub mod method;
 pub mod method_handle;
+pub mod py_utils;
 pub mod scalar;
 pub mod value;
 
@@ -76,6 +77,9 @@ fn androscalpel(py: Python, m: &PyModule) -> PyResult<()> {
     let ins_module = PyModule::new(py, "ins")?;
     androscalpel_ins(py, ins_module)?;
     m.add_submodule(ins_module)?;
+    let utils_module = PyModule::new(py, "utils")?;
+    py_utils::export_module(py, utils_module)?;
+    m.add_submodule(utils_module)?;
 
     Ok(())
 }
diff --git a/androscalpel/src/py_utils.rs b/androscalpel/src/py_utils.rs
new file mode 100644
index 0000000..5c2fee5
--- /dev/null
+++ b/androscalpel/src/py_utils.rs
@@ -0,0 +1,53 @@
+//! Function that are can be usefull on the python side.
+
+use pyo3::prelude::*;
+use pyo3::types::PyBytes;
+
+use crate::Result;
+use androscalpel_serializer::{Serializable, Sleb128, Uleb128, Uleb128p1};
+
+/// Convert an integer to the uleb128 byte encoding
+#[pyfunction]
+pub fn int_to_uleb128(py: Python, x: u32) -> Result<PyObject> {
+    Ok(PyBytes::new(py, &Uleb128(x).serialize_to_vec()?).into())
+}
+
+/// Convert an integer to the uleb128p1 byte encoding
+#[pyfunction]
+pub fn int_to_uleb128p1(py: Python, x: u32) -> Result<PyObject> {
+    Ok(PyBytes::new(py, &Uleb128p1(x).serialize_to_vec()?).into())
+}
+/// Convert an integer to the sleb128 byte encoding
+#[pyfunction]
+pub fn int_to_sleb128(py: Python, x: i32) -> Result<PyObject> {
+    Ok(PyBytes::new(py, &Sleb128(x).serialize_to_vec()?).into())
+}
+
+/// Decode an uleb128 encoded integer
+#[pyfunction]
+pub fn uleb128_to_int(b: &[u8]) -> Result<u32> {
+    Ok(Uleb128::deserialize_from_slice(b)?.0)
+}
+
+/// Decode an uleb128p1 encoded integer
+#[pyfunction]
+pub fn uleb128p1_to_int(b: &[u8]) -> Result<u32> {
+    Ok(Uleb128p1::deserialize_from_slice(b)?.0)
+}
+
+/// Decode an sleb128 encoded integer
+#[pyfunction]
+pub fn sleb128_to_int(b: &[u8]) -> Result<i32> {
+    Ok(Sleb128::deserialize_from_slice(b)?.0)
+}
+
+/// export the function in a python module
+pub(crate) fn export_module(_py: Python, m: &PyModule) -> PyResult<()> {
+    m.add_function(wrap_pyfunction!(int_to_uleb128, m)?)?;
+    m.add_function(wrap_pyfunction!(int_to_uleb128p1, m)?)?;
+    m.add_function(wrap_pyfunction!(int_to_sleb128, m)?)?;
+    m.add_function(wrap_pyfunction!(uleb128_to_int, m)?)?;
+    m.add_function(wrap_pyfunction!(uleb128p1_to_int, m)?)?;
+    m.add_function(wrap_pyfunction!(sleb128_to_int, m)?)?;
+    Ok(())
+}